Statics-Chapters 1-6

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Which scatter diagram indicates a perfect positive correlation? A) b B) a C) f D) c

A)

The following is a sample of 19 November utility bills (in dollars) from a neighborhood.What is the largest bill in the sample that would not be considered an outlier? 52, 62, 66, 68, 72, 74, 76, 76, 76, 78, 78, 82, 84, 84, 86, 88, 92, 96, 110 A) $86 B) $96 C) $95 D) $88

B)

The least squares regression line A) maximizes the mean difference between the residuals squared. B) minimizes the sum of the residuals squared. C) maximizes the sum of the residuals squared. D) minimizes the mean difference between the residuals squared

B)

Which measure of central tendency is not resistant to extreme values in a numeric data set? A) Median B) Parameters C) Mean D) Mode

C)

Cohort Studies

A cohort study first identifies a group of individuals to participate in the study (the cohort). The cohort is then observed over a long period of time. Over this time period, characteristics about the individuals are recorded. Because the data is collected over time, cohort studies are prospective

the day of the month A) nominal B) ordinal C) interval D) ratio

C) interval

the year of manufacture of a car A) ratio B) ordinal C) interval D) nominal

C) interval

height of a tree A) ordinal B) nominal C) ratio D) interval

C) ratio

Guidelines for Determining the Lower Class Limit of the First Class and Class Width

ClassW= largest data value- smallest data value -------------------------------------------- number of classes Round this value up to a convenient numbe

) Find the equation of the regression line for the given data. Round values to the nearest thousandth. A) y ^ = 0.522x - 2.097 B) y ^ = 2.097x + 0.552 C) y ^ = -0.552x + 2.097 D) y ^ = 2.097x - 0.552

D)

A market researcher randomly selects 100 homeowners under 55 years of age and 100 homeowners over 55 years of age. What sampling technique was used? A) systematic B) cluster C) convenience D) simple random E) stratified

E) stratified

Compute the Probability of an Event Using the Complement Rule

Let S denote the sample space of a probability experiment and let Edenote an event. The complement of E, denoted EC, is all outcomes in the sample space S that are not outcomes in the event

The median of a variable is the

value that lies in the middle of the data when arranged in ascending order

response variable

a variable that measures an outcome or result of a study

explanatory variable

a variable that we think explains or causes changes in the response variable

Determine whether the quantitative variables are discrete or continuous. (a) The number of heads obtained after flipping a coin five times. (b) The number of cars that arrive at a McDonald's drive-thru between 12:00 p.m. and 1:00 p.m. (c) The distance a 2014 Toyota Prius can travel in city driving conditions with a full tank of gas.

a.discrete b.discrete c. continuous (measurable, miles, ft, inches,grams)

For each of the following variables, determine the level of measurement. (a) Gender (b) Temperature (c) Number of days during the past week that a college student studied (d) Letter grade earned in your statistics class

a.nominal b.interval c.ratio d.ordinal

The subjective probability of an outcome is a probability obtained on the

basis of personal judgment. For example, an economist predicting there is a 20% chance of recession next year would be a subjective probabi

If a researcher assigns the individuals in a study to a certain group, intentionally changes the value of an explanatory variable, and then records the value of the response variable for each group, the study is a

designed experiment

A histogram is constructed by

drawing rectangles for each class of data. The height of each rectangle is the frequency or relative frequency of the class. The width of each rectangle is the same and the rectangles touch each other

Because the mean of a random variable represents what we would expect to happen in the long run, it is also called the

expected value, E(X), of the random variable

To design an experiment means to describe the overall plan in conducting the

experiment

a person or object that is a member of the population being studied

individual

An experiment is a controlled study conducted to determine the effect varying

one or more explanatory variables or factors has on a response variable. Any combination of the values of the factors is called a treatment.

A matched-pairs design is an experimental design in which the experimental units are

paired up. The pairs are matched up so that they are somehow related (that is, the same person before and after a treatment, twins, husband and wife, same geographical location, and so on). There are only two levels of treatment in a matched-pairs design

The experimental unit (or subject) is a

person, object or some other well-defined item upon which a treatment is applied

The entire group to be studied is called the

population

a subset of the population that is being studied

sample

Random sampling is the process of using chance to

select individuals from a population to be included in the sample -If convenience is used to obtain a sample, the results of the survey are meaningless

Uniform distribution

the frequency of each value of the variable is evenly spread out across the values of the variable

conditional Probability and the General Multiplication Rule

the probability of E and F is the probability of event E occurring times the probability of event F occurring, given the occurrence of event E.

Standard Deviation of a Discrete Random Variable

the square root of the variance

A study was designed to investigate the effects of two variables - (1) a student's level of mathematical anxiety and (2) teaching method - on a student's achievement in a mathematics course. Students who had a low level of mathematical anxiety were taught using the traditional expository method. These students obtained a mean score of 460 with a standard deviation of 20 on a standardized test. Assuming a bell-shaped distribution, what percentage of scores exceeded 420? A) approximately 97.5% B) approximately 84% C) approximately 95% D) approximately 2.5%

A)

In distributions that are skewed to the left, what is the relationship of the mean, median, and mode? A) mode > median > mean B) mode < mean < median C) mean > median > mode D) mode > mean > median

A)

the weight of a player on the wrestling team A) continuous B) discrete

A) continuous

the number of phone calls to the police department on any given day A) discrete B) continuous

A) discrete

the number of pills in an aspirin bottle A) discrete B) continuous

A) discrete

An instructor wishes to determine if there is a relationship between the number of absences from his class and a student's final grade in the course. What is the explanatory variable? A) The instructor's point scale for attendance B) Absences C) Student's performance on the final examination D) Final Grade

B)

Choose the coefficient of determination that matches the scatterplot. Assume that the scales on the horizontal and vertical axes are the same. A) R2 = 0.41 B) R2 = 0.097 C) R2 = -0.31 D) R2 = 0.76

B)

Classify the statement as an example of classical probability, empirical probability, or subjective probability. The probability that cab fares will rise during the winter is 0.05. A) empirical probability B) subjective probability C) classical probability

B)

Compute the linear correlation coefficient between the two variables and determine whether a linear relation exists x 5 7 14 11 9 8 10 12 13 6 y -11 -9 8 0 -3 -7 -2 2 5 -9 A) r = 0.819; linear relation exists B) r = 0.990; linear relation exists C) r = 0.881; no linear relation exists D) r = 0.792; no linear relation exists

B)

Compute the sum of the squared residuals of the least-squares line for the given data. A) 1.036 B) 7.624 C) 0 D) 2.097

B)

The regression line for the given data is y ^ = 5.044x + 56.11. Determine the residual of a data point for which x =6 and y = 90. A) 176.374 B) 3.626 C) -504.07 D) 86.374

B)

) If X1, X2, X3, ..., XN are the N observations of a variable from a population, then the population mean is symbolized by A) μ B) Σ - C) X D) X

A)

the speed of a car on a Boston tollway during rush hour traffic A) discrete B) continuous

B) continuous

Approximating Probabilities Using the Empirical Approach The probability of an event E is approximately the

number of times event E is observed divided by the number of repetitions of the experiment

A systematic sample is obtained by

selecting every kth individual from the population. The first individual selected is a random number between 1 and k

According to government data, the probability that an adult was never in a museum is 13%. In a random survey of 20 adults, what is the mean and standard deviation of the number that were never in a museum? A) mean: 2.6; standard deviation: 1.50399468 B) mean: 2.6; standard deviation: 1.61245155 C) mean: 17.4; standard deviation: 1.50399468 D) mean: 17.4 standard deviation: 1.61245155

A)

After completing an inventory of three warehouses, a golf club shaft manufacturer described its stock of 12,246 shafts with the percentages given in the table. Suppose a shaft is selected at random from the 12,246 currently in stock, and the warehouse number and type of shaft are observed. Given that the shaft is produced in warehouse 2, find the probability it has an extra stiff shaft. A) 0.419 B) 0.351 C) 0.37 D) 0.684

A)

Calculate the linear correlation coefficient for the data below. A) -0.995 B) -0.671 C) -0.885 D) -0.778

A)

Quantitative variables classify individuals in a sample according to A) numerical measure. B) exhibited trait. C) physical attribute. D) personality characteristic.

A)

The random variable x represents the number of girls in a family of three children. Assuming that boys and girls are equally likely, find the mean and standard deviation for the random variable x. A) mean: 1.50; standard deviation: 0.87 B) mean: 2.25; standard deviation: 0.76 C) mean: 2.25; standard deviation: 0.87 D) mean: 1.50; standard deviation: 0.76

A)

The table below represents a random sample of the number of deaths per 100 cases for a certain illness over time. If a person infected with this illness is randomly selected from all infected people, find the probability that the person lives 3-4 years after diagnosis. Express your answer as a simplified fraction and as a decimal. A) 35/100 ; 0.35 B) 1 /35 ; 0.029 C) 7/ 120 ; 0.058 D) 35 /65 ; 0.538

A)

A pollster obtains a sample of students and asks them how they will vote on an upcoming referendum. A) observational study B) experiment

A) observational study

Every fifth adult entering an airport is checked for extra security screening. What sampling technique is used? A) systematic B) cluster C) convenience D) stratified E) simple random

A) systematic

The Law of Large Numbers

As the number of repetitions of a probability experiment increases, the proportion with which a certain outcome is observed gets closer to the probability of the outcome.

When data appear rather bunched, we can use split stems

As with the determination of class intervals in the creation of frequency histograms, judgment plays a major role.There is no such thing as the correct stem-and-leaf plot. However, some plots are better than others

) The below table shows the probabilities generated by rolling one die 50 times and noting the up face. What is the probability of getting an odd up face? Roll 1 2 3 4 5 6 Probability 0.22 0.10 0.18 0.12 0.18 0.20 A) 0.42 B) 0.58 C) 0.50 D) 0.55

B)

A quiz consists of 10 multiple choice questions, each with five possible answers, one of which is correct. To pass the quiz a student must get 60% or better on the quiz. If a student randomly guesses, what is the probability that the student will pass the quiz? A) 0.205 B) 0.006 C) 0.377 D) 0.060

B)

Determine the number of classes in the frequency table below. Class Frequency 23-24 7 25-26 2 27-28 6 29-30 4 31-32 1 A) 2 B) 5 C) 20 D) 6

B)

For a given data set, the equation of the least squares regression line will always pass through A) at least two point in the given data set. B) (x, y). C) the y-intercept and the slope. D) every point in the given data set.

B)

Given the equation of a regression line is y= 5x - 10, what is the best predicted value for y given x = 2? A) 20 B) 0 C) 15 D) -3

B)

Given the following five-number summary, find the interquartile range. 29, 37, 50, 66, 94 A) 50 B) 29 C) 65 D) 32.5

B)

The coefficient of correlation between x and y is r = 0.59. Calculate the coefficient of determination R2. Round R2 to the nearest hundredth. A) 0.65 B) 0.35 C) 0.41 D) 0.59

B)

With which model was the greatest percentage satisfied? Estimate the empirical probability that a person with this model is very satisfied with the experience. Express the answer as a fraction with a denominator of 100 A) Model F; 57/100 B) Model A; 81/100 C) Model A: 0.81/100 D) Model F; 0.57/100

B)

) A travel industry researcher interviews all of the passengers on five randomly selected cruises. What sampling technique is used? A) convenience B) cluster C) systematic D) stratified E) simple random

B) cluster

the bank account numbers of the students in a class A) quantitative B) qualitative

B) qualitative

A drug company wanted to test a new indigestion medication. The researchers found 400 adults aged 25-35 and randomly assigned them to two groups. The first group received the new drug, while the second received a placebo. After one month of treatment, the percentage of each group whose indigestion symptoms decreased was recorded and compared. What is the treatment in this experiment? A) the percentage who had decreased indigestion symptoms B) the 400 adults aged 25-35 C) the drug D) the one month treatment time

C)

A group of students were asked if they carry a n ATM card The responses are listed in the table. If a student is selected at random, find the probability that he or she owns an ATM card given that the student is a freshman. Round your answer to three decimal places. Round your answer to the nearest thousandth. A) 0.719 B) 0.317 C) 0.683 D) 0.410

C)

A residual is the difference between A) the observed value of y and the predicted value of x. B) the observed value of x and the predicted value of y. C) the observed value of y and the predicted value of y. D) the observed value of x and the predicted value of x.

C)

A sample of 255 shoppers at a large suburban mall were asked two questions: (1) Did you see a television ad for the sale at department store X during the past 2 weeks? (2) Did you shop at department store X during the past 2 weeks? The responses to the questions are summarized in the table. What is the probability that a randomly selected shopper from the 255 questioned did not shop at department store X? Round the the nearest thousandth. A) 0.078 B) 0.647 C) 0.353 D) 0.275

C)

Classify the statement as an example of classical probability, empirical probability, or subjective probability. In one state lottery, a person selects a 4-digit number. The probability of winning this state's lottery is 1 10,000 . A) empirical probability B) subjective probability C) classical probability

C)

The measures the percentage of total variation in the response variable that is explained by the least squares regression line. A) slope of the regression line B) coefficient of linear correlation C) coefficient of determination D) sum of the residuals squared

C)

The regression line for the given data is y ^ = -0.206x + 2.097. Determine the residual of a data point for which x = 4 and y = 8. A) 1.273 B) 3.551 C) 6.727 D) 9.273

C)

Two dice are rolled. What is the probability of having both faces the same (doubles) or a total of 4 or 10? Round to the nearest hundredth. A) 0.15 B) 0.33 C) 0.28 D) 0.06

C)

Describe the shape of the distribution. A) bell shaped B) uniform C) skewed to the left D) skewed to the right

C) skewed to the left

Describe the shape of the distribution. A) bell shaped B) skewed to the left C) skewed to the right D) uniform

C) skewed to the right

Explain what is misleading about the graphic. The volume of our sales has doubled!!! A) The length of a side has doubled, but the area has been unchanged. B) The length of a side has doubled, but the area has been multiplied by 8. C) The length of a side has doubled, but the area has been multiplied by 4. D) The graphic is not misleading.

C.

Make a scatter diagram for the data. Use the scatter diagram to describe how, if at all, the variables are related. x 3 1 -4 0 -1 5 -2 y 19 21 17 20 23 19 26

D)

Many firms use on-the-job training to teach their employees new software. Suppose you work in the personnel department of a firm that just finished training a group of its employees in new software, and you have been requested to review the performance of one of the trainees on the final test that was given to all trainees. The mean of the test scores is 72. Additional information indicated that the median of the test scores was 76. What type of distribution most likely describes the shape of the test scores? A) unable to determine with the information given B) skewed to the right C) symmetric D) skewed to the left

D)

Suppose that E and F are two events and that P(E and F) = 0.32 and P(E) = 0.8. What is P(F/E)? A) 0.256 B) 1.12 C) 2.5 D) 0.4

D)

The ________ of a variable is computed by determining the sum of all the values of the variable in the data set and dividing this sum by the number of observations in the data set. A) Mode B) Geometric mean C) Median D) Arithmetic mean

D)

The probability that a football game will go into overtime is 17%. What is the probability that two of three football games will go to into overtime? A) 0.0289 B) 0.17 C) 0.351 D) 0.072

D)

The probability that an individual has 20-20 vision is 0.13. In a class of 16 students, what is the probability of finding five people with 20-20 vision? A) 0.313 B) 0.000 C) 0.13 D) 0.035

D)

he table below summarizes the weights of the almonds (in grams) in a one-pound bag. What is the class width? Weight (g) Frequency 0.7585 -0.8184 1 0.8185 -0.8784 1 0.8785 -0.9384 1 0.9385 -0.9984 3 0.9985 -1.0584 157 1.0585 -1.1184 171 1.1185 -1.1784 8 A) 0.4 B) 0.408 C) 0.059 D) 0.06

D)

The variable measured in the experiment is called ____________ . A) the predictor variable B) a sampling unit C) the treatment D) the response variable

D)

According to government data, the probability that an adult was never in a museum is 15%. In a random survey of 10 adults, what is the probability that two or fewer were never in a museum? A) 0.800 B) 0.200 C) 0.002 D) 0.820

D)

A variable that is related to either the response variable or the predictor variable or both, but which is excluded from the analysis is a A) lurking variable. B) discrete variable. C) random variable. D) qualitative variable.

A)

Find the probability that of 25 randomly selected housewives, no two share the same birthday. Round your answer to the nearest thousandth. A) 0.431 B) 0.068 C) 0.569 D) 0.995

A)

Given the following five-number summary, find Q1. 2.9, 5.7, 10.0, 13.2, 21.1. A) 5.7 B) 10.0 C) 2.9 D) 13.2

A)

The colors of book covers on a bookshelf A) qualitative B) quantitative

A) qualitative

Given the table of probabilities for the random variable x, does this form a probability distribution? Answer Yes or No. A) No B) Yes

B)

If the graph of a distribution of data shows that the graph is skewed to the left then the A) No conclusion about the relative position of the mean and the median can be made B) Median > Mean C) Mean > Median D) Mean ≈ Median

B)

The table below shows the probabilities generated by rolling one die 50 times and recording the number rolled. Are the events A = { roll an odd number } and B = {roll a number less than or equal to two} disjoint? Roll 1 2 3 4 5 6 Probability 0.22 0.10 0.18 0.12 0.18 0.20 A) Yes B) No

B)

the weights of cases loaded onto an airport conveyor belt A) qualitative B) quantitative

B) quantitative

capacity of a backpack A) ordinal B) ratio C) nominal D) interval

B) ratio

According to government data, the probability that an adult was never in a museum is 15%. In a random survey of 10 adults, what is the probability that at least eight were in a museum? A) 0.800 B) 0.200 C) 0.820 D) 0.002

C)

Consider the discrete probability distribution to the right when answering the following question. Find the probability that x exceeds 5 A) 0.78 B) 0.27 C) 0.51 D) 0.49

C)

The probability that a house in an urban area will develop a leak is 5%. If 20 houses are randomly selected, what is the mean of the number of houses that developed leaks? A) 1.5 B) 0.5 C) 1 D) 2

C)

Which measure of central tendency may not exist for all numeric data sets? A) Midrange B) Median C) Mode D) Mean

C)

A time-series plot is obtained by

plotting the time in which a variable is measured on the horizontal axis and the corresponding value of the variable on the vertical axis. Line segments are then drawn connecting the points

The variance of a variable is the square of the

standard deviation. The population variance is σ2 and the sample variance is s2

least squares regression line

the line that makes the sum of the squared residuals as small as possible

Skewed left

the tail to the left of the peak is longer than the tail to the right of the pea

The Empirical Rule

•Approximately 68% of the data will lie within 1 standarddeviation of the mean. That is, approximately 68% of the data lie between μ− 1σ and μ + 1σ. •Approximately 95% of the data will lie within 2 standard deviations of the mean. That is, approximately 95% of the data lie between μ − 2σ and μ + 2σ. •Approximately 99.7% of the data will lie within 3 standard deviations of the mean. That is, approximately 99.7% of the data lie between μ− 3σ and μ + 3σ

The population arithmetic mean, μ (pronounced "mew"), is computed using

all the individuals in a population.The population mean is a parameter

uniform shape

mean and median are equal

The mode of a variable is the

most frequent observation of the variable that occurs in the data set. A set of data can have no mode, one mode, or more than one mode. If no observation occurs more than once, we say the data have no mode

Suppose that E and F are two events and that N(E and F) = 290 and N(E) = 650. What is P(F E)? A) 0.446 B) 0.045 C) 0.309 D) 2.241

A)

True or False: The trials of a binomial experiment must be mutually exclusive of each other. A) True B) False

B)

Calculate the linear correlation coefficient for the data below A) -0.581 B)-0.549 C) -0.104 D) -0.132

C)

At a local technical school, five auto repair classes are randomly selected and all of the students from each class are interviewed. What sampling technique is used? A) systematic B) stratified C) cluster D) convenience E) simple random

C) cluster

Find the z-score for the value 66, when the mean is 51 and the standard deviation is 1. A) z = 14.00 B) z = 1.27 C) z = -1.27 D) z = 15.00

D)

A sample consists of every 20th worker from a group of 5000 workers. What sampling technique was used? A) stratified B) simple random C) cluster D) systematic E) convenience

D) systematic

The upper class limit of a class is the

largest value within the class

The data below are the final exam scores of 10 randomly selected calculus students and the number of hours they slept the night before the exam. Calculate the linear correlation coefficient. A) 0.761 B) 0.654 C) 0.991 D) 0.847

D)

A drug company wanted to test a new depression medication. The researchers found 400 adults aged 25-35 and randomly assigned them to two groups. The first group received the new drug, while the second received a placebo. After one month of treatment, the percentage of each group whose depression symptoms decreased was recorded and compared. What type of experimental design is this? A) completely randomized design B) matched-pairs design C) single-blind design D) randomized block design

A)

A lab orders a shipment of 100 rats a week, 52 weeks a year, from a rat supplier for experiments that the lab conducts. Prices for each weekly shipment of rats follow the distribution below: Price $10.00 $12.50 $15.00 Probability 0.4 0.25 0.35 How much should the lab budget for next year's rat orders assuming this distribution does not change. (Hint: find the expected price.) A) $643.50 B) $1238.00 C) $3,346,200.00 D) $12.38

A)

A manager wishes to determine the relationship between the number of miles traveled (in hundreds of miles) by her sales representatives and their amount of sales (in thousands of dollars) per month. Find the equation of the regression line for the given data. What would be the predicted sales if the sales representative traveled 0 miles? Is this reasonable? Why or why not? A) y ^ = 3.53x + 37.92; $37,920; No; it is not reasonable for a representative to travel 0 miles and have a positive amount of sales. B) y ^ = 37.92x + 3.53; $3792; Yes, it is reasonable. C) y ^ = 3.53x + 37.92; $3792; No; it is not reasonable for a representative to travel 0 miles and have a positive amount of sales. D) y ^ = 3.53x + 37.92; $37,920; Yes, it is reasonable

A)

A manager wishes to determine whether there is a relationship between the number of years her sales representatives have been with the company and their average monthly sales. The table shows the years of service for each of her sales representatives and their average monthly sales (in thousands of dollars). Years with company, x 2 3 10 7 8 15 3 1 11 Sales , y 40 42 87 71 74 70 57 64 129 A) r = 0.632; no linear relation exists B) r = 0.717; no linear relation exists C) r = 0.632; linear relation exists D) r = 0.717; linear relation exists

A)

A probability experiment is conducted in which the sample space of the experiment is S = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}. Let event A = {4, 5, 6, 7} and event B = {10, 11, 12}. Assume that each outcome is equally likely. List the outcomes in A and B. Are A and B mutually exclusive? A) { }; yes B) {4, 5, 6, 7, 10, 11, 12}; yes C) { }; no D) {4, 5, 6, 7, 10, 11, 12}; no

A)

A severe drought affected several western states for 3 years. A Christmas tree farmer is worried about the drought's effect on the size of his trees. To decide whether the growth of the trees has been retarded, the farmer decides to take a sample of the heights of 25 trees and obtains the following results (recorded in inches): 60 57 62 69 46 54 64 60 59 58 75 51 49 67 65 44 58 55 48 62 63 73 52 55 50 Which measure of central tendency would be considered the best measure to use in this problem? A) mean B) mode C) range D) median

A)

A single die is rolled twice. The set of 36 equally likely outcomes is {(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6), (2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6), (3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6), (4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (4, 6), (5, 1), (5, 2), (5, 3), (5, 4), (5, 5), (5, 6), (6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)}. Find the probability of getting two numbers whose sum is greater than 9 and less than 13. A) 1/6 B) 5/36 C) 7/36 D) 0

A)

A single die is rolled twice. The set of 36 equally likely outcomes is {(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6), (2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6), (3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6), (4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (4, 6), (5, 1), (5, 2), (5, 3), (5, 4), (5, 5), (5, 6), (6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)}. Find the probability of getting two numbers whose sum is greater than 9 and less than 13. A) 1/6 B) 5/36 C) 7/36 D) 0

A)

An Apple Pie Company knows that the number of pies sold each day varies from day to day. The owner believes that on 50% of the days she sells 100 pies. On another 25% of the days she sells 150 pies, and she sells 200 pies on the remaining 25% of the days. To make sure she has enough product, the owner bakes 200 pies each day at a cost of $2 each. Assume any pies that go unsold are thrown out at the end of the day. If she sells the pies for $5 each, find the probability distribution for her daily profit.

A)

At a tennis tournament a statistician keeps track of every serve. The statistician reported that the mean serve speed of a particular player was 102 miles per hour (mph) and the standard deviation of the serve speeds was 15 mph. If nothing is known about the shape of the distribution, give an interval that will contain the speeds of at least three-fourths of the player's serves. A) 72 mph to 132 mph B) 132 mph to 162 mph C) 57 mph to 147 mph D) 87 mph to 117 mph

A)

Choose the coefficient of determination that matches the scatterplot. Assume that the scales on the horizontal and vertical axes are the same. A) R2 = 0.77 B) R2 = 0.38 C) R2 = 0.51 D) R2 = 0.96

A)

Classify the following random variable: telephone area codes A) qualitative data B) quantitative discrete data C) experimental data D) quantitative continuous data

A)

Fifty percent of the people that use the Internet order something online. Find the probability that only two of 9 Internet users will order something online. A) 0.070 B) 0.002 C) 9.000 D) 0.222

A)

Given the bar graph shown below, the Pareto chart that would best represent the data should have the bars in the following order. A) D A E C F B B) C A D E F B C) B F C E A D D) B F E D A C

A)

In a 1-pond bag of skittles the possible colors were red, green, yellow, orange, and purple. The probability of drawing a particular color from that bag is given below. Is this a probability model? Answer Yes or No. A) Yes B) No

A)

In a recent survey, 70% of the community favored building a health center in their neighborhood. If 14 citizens are chosen, find the probability that exactly 9 of them favor the building of the health center. A) 0.196 B) 0.007 C) 0.700 D) 0.643

A)

In a recent survey, 80% of the community favored building a health center in their neighborhood. If 15 citizens are chosen, what is the mean number favoring the health center? A) 12 B) 10 C) 15 D) 8

A)

In a sandwich shop, the following probability distribution was obtained. The random variable x represents the number of condiments used for a hamburger. Find the mean and standard deviation for the random variable x. x P(x) 0 0.30 1 0.40 2 0.20 3 0.06 4 0.04 A) mean: 1.14; standard deviation: 1.04 B) mean: 1.30; standard deviation: 2.38 C) mean: 1.54; standard deviation: 1.30 D) mean: 1.30; standard deviation: 1.54

A)

In a study of feeding behavior, zoologists recorded the number of grunts of a warthog feeding by a lake in a 15 minute time period following the addition of food. The data showing the weekly number of grunts and the age of the warthog (in days) are listed below. Compute the sum of the squared residuals of the least squared line for the given data. A) 5533.53 B) 74.39 C) 188.84 D) 13.74

A)

In an area of the Great Plains, records were kept on the relationship between the rainfall (in inches) and the yield of wheat (bushels per acre). Which is the best predicted value for y given x = 7.1? A) 35.4 B) 35.2 C) 35.7 D) 35.9

A)

In order for a company's employees to work for the foreign office, they must take a test in the language of the country where they plan to work. The data below show the relationship between the number of years that employees have studied a particular language and the grades they received on the proficiency exam. What is the best predicted value for y given x = 3.5? A) 70 B) 66 C) 72 D) 68

A)

Is either histogram symmetric? A) Neither is symmetric. B) The first is symmetric, but the second is not symmetric. C) Both are symmetric. D) The second is symmetric, but the first is not symmetric.

A)

The ______________ probability of an outcome is obtained by dividing the number of ways an event can occur by the number of possible outcomes. A) Classical B) Conditional C) Subjective D) Empirical

A)

The data below are the average one-way commute times (in minutes) for selected students and the number of absences for those students during the term. Find the equation of the regression line for the given data. What would be the predicted number of absences if the commute time was 95 minutes? Is this a reasonable question? Round the predicted number of absences to the nearest whole number. Round the regression line values to the nearest hundredth. A) y ^ = 0.45x - 30.27; 12 absences; Yes, it is reasonable. B) y ^ = 0.45x + 30.27; 73 absences; No, it is not reasonable. 95 minutes is well outside the scope of the model. C) y ^ = 0.45x + 30.27; 73 absences; Yes, it is reasonable. D) y ^ = 0.45x - 30.27; 12 absences; No, it is not reasonable. 95 minutes is well outside the scope of the model.

A)

The overnight shipping business has skyrocketed in the last ten years. The single greatest predictor of a company's success has been proven time and again to be customer service. A study was conducted to study the customer satisfaction levels for one overnight shipping business. In addition to the customer's satisfaction level, the customers were asked how often they used overnight shipping. The results are shown below in the following table. What is the probability that a respondent did not have a medium level of satisfaction with the company? Round the the nearest hundredth A) 0.69 B) 0.29 C) 0.71 D) 0.31

A)

The policy committee at State University has 6 members: Dr. Hernandez, LaToyna, Ming, Jose, John, and Prof. Rise. A subcommittee of two members must be formed to investigate the visitation policy in the dormitories. List all possible simple random samples of size 2. A) Dr. Hernandez and LaToyna, Dr. Hernandez and Ming, Dr. Hernandez and Jose, Dr. Hernandez and John, Dr. Hernandez and Prof. Rise, LaToyna and Ming, LaToyna and Jose, LaToyna and John, LaToyna and Prof. Rise, Ming and Jose, Ming and John, Ming and Prof. Rise, Jose and John, Jose and Prof. Rise, John and Prof. Rise B) Dr. Hernandez and LaToyna, LaToyna and Ming, Ming and Jose, Jose and John, John and Prof. Rise C) Dr. Hernandez and LaToyna, Dr. Hernandez and Ming, Dr. Hernandez and Jose, Dr. Hernandez and John, Dr. Hernandez and Prof. Rise D) Dr. Hernandez and LaToyna, Ming and Jose, John and Prof. Rise

A)

The probability that event A will occur is P(A) = Number of successful outcomes Total number of all possible outcomes A) True B) False

A)

The produce manager at a farmer's market was interested in determining how many oranges a person buys when they buy oranges. He asked the cashiers over a weekend to count how many oranges a person bought when they bought oranges and record this number for analysis at a later time. The data is given below in the table. The random variable x represents the number of oranges purchased and P(x) represents the probability that a customer will buy x apples. Determine the mean number of oranges purchased by a customer A) 3.97 B) 5.50 C) 4 D) 3

A)

The random variable x represents the number of computers that families have along with the corresponding probabilities. Find the mean and standard deviation for the random variable x. x P(x) 0 0.49 1 0.05 2 0.32 3 0.07 4 0.07 A) mean: 1.18; standard deviation: 1.30 B) mean: 1.39; standard deviation: 0.64 C) mean: 1.18; standard deviation: 0.64 D) mean: 1.39; standard deviation: 0.80

A)

The regression line for the given data is y = 4.379x + 4.267. Determine the residual of a data point for which x = 12.5 and y = 59. A) -0.0045 B) -250.128 C) 118.0045 D) 59.0045

A)

The scores from a state standardized test have a bell-shaped distribution with a mean of 100 and a standard deviation of 15. Use the Empirical Rule to find the percentage of students with scores between 70 and 130. A) 95% B) 100% C) 99.7% D) 68%

A)

The table below shows the ages and weights (in pounds) of 9 randomly selected tennis coaches. A) r = 0.960; linear relation exists B) r = 0.908; no linear relation exists C) r = 0.908; linear relation exists D) r = 0.960; no linear relation exists

A)

The table lists the drinking habits of a group of college students. If a student is chosen at random, find the probability of getting someone who is a man or a woman. Round your answer to three decimal places. Sex Non-drinker Regular Drinker Heavy Drinker Total Man 135 59 5 199 Woman 187 21 14 222 Total 322 80 19 421 A) 1 B) 0.235 C) 0.765 D) 0.917

A)

The table lists the drinking habits of a group of college students. If a student is chosen at random, find the probability of getting someone who is a non-drinker. Round your answer to three decimal places A) 0.770 B) 0.919 C) 0.230 D) 1

A)

To eliminate the effects of either the row or the column variables in a contingency table, a_____________distribution is created. A) marginal B) Student's t C) χ2 D) normalized

A)

True or False: A doctor wishes to determine the relationship between a male's age and that male's total cholesterol level. He tests 200 males and records each male's age and that male's total cholesterol level. The males cholesterol level is the explanatory variable? A) False B) True

A)

We believe that 95% of the population of all Calculus I students consider calculus an exciting subject. Suppose we randomly and independently selected 20 students from the population. If the true percentage is really 95%, find the probability of observing 19 or more of the students who consider calculus to be an exciting subject in our sample of 20. A) 0.735840 B) 0.377354 C) 0.358486 D) 0.264160

A)

Which measure of central tendency is more representative of the typical observation if the graph of the data is skewed to the right? A) Median B) Mean C) Midrange D) Mode

A)

You are dealt one card from a standard 52-card deck. Find the probability of being dealt a picture card. A) 3/13 B) 3/52 C) 3/26 D) 1/13

A)

the number of emails received on any given day A) discrete B) continuous

A)

he low temperature in degrees Fahrenheit on January 1st in Cheyenne, Wyoming A) continuous B) discrete

A) continuous

Based on 9500 responses from 29,000 questionnaires sent to all its members, a major medical association estimated that the annual salary of its members was $98,500 per year. What sampling technique was used? A) simple random B) convenience C) cluster D) systematic E) stratified

A) simple random

The distribution of Bachelor's degrees conferred by a university is listed in the table. Assume that a student majors in only one subject. What is the probability that a randomly selected student with a Bachelor's degree majored in Business, Chemistry or Engineering? Round your answer to three decimal places. Major Frequency Physics 216 Philosophy 207 Engineering 86 Business 180 Chemistry 227 A) 0.462 B) 0.538 C) 0.290 D) 0.342

B)

The following Venn diagram is for the six sample points possible when rolling a fair die. Let A be the event rolling an even number and let B be the event rolling a number greater than 1. Which of the following events describes the event rolling a 1? A) Ac B) Bc C) A ∪ B D) B

B)

The following data represent the living situation of newlyweds in a large metropolitan area and their annual household income. What percent of people who make between $20,000 and $35,000 per year own their own home? Round to the nearest tenth of a percent A) 4.5% B) 27.8% C) 36.9% D) 35.3%

B)

The managers of a corporation were surveyed to determine the background that leads to a successful manager. Each manager was rated as being either a good, fair, or poor manager by his/her boss. The manager's educational background was also noted. The data appear below. Given that a manager is only a fair manager, what is the probability that this manager has no college background? A) 1/2 B) 5/87 C) 1/32 D) 23/40

B)

The probability that a house in an urban area will develop a leak is 6%. If 24 houses are randomly selected, what is the probability that none of the houses will develop a leak? A) 0.003 B) 0.227 C) 0.060 D) 0.000

B)

The probability that an individual has 20-20 vision is 0.13. In a class of 90 students, what is the mean and standard deviation of the number with 20-20 vision in the class? A) mean: 90; standard deviation: 3.19045451 B) mean: 11.7; standard deviation: 3.19045451 C) mean: 90; standard deviation: 3.42052628 D) mean: 11.7; standard deviation: 3.42052628

B)

The regression line for the given data is y = -1.885x + 0.758. Determine the residual of a data point for which x = 2 and y = -4. A) -3.012 B) -0.988 C) -7.012 D) -6.298

B)

The repair costs for five cars which were crashed by a safety testing organization were as follows: $100, $150, $200, $250, and $150. Find the mean cost of repair. A) $160 B) $170 C) $180 D) $140

B)

The weights (in pounds) of babies born at St Mary's hospital last month are summarized in the table. Weight (lb) Number of Babies 5.0 - 5.8 8 5.9 - 6.7 20 6.8 - 7.6 18 7.7 - 8.5 10 8.6 - 9.4 4 Find the class limits for the second class. A) lower limit: 5.85; upper limit:6.75 B) lower limit: 5.9; upper limit: 6.7 C) lower limit: 5.8; upper limit: 6.8 D) lower limit: 5.9; upper limit: 6.8

B)

This problem deals with eye color, an inherited trait. For purposes of this problem, assume that only two eye colors are possible, brown and blue. We use b to represent a blue eye gene and B a brown eye gene. If any B genes are present, the person will have brown eyes. The table shows the four possibilities for the children of two Bb (brown-eyed) parents, where each parent has one of each eye color gene. Second Parent First Parent B b B BB Bb b Bb bb Find the probability that these parents give birth to a child who has blue eyes. A) 1/2 B) 1/4 C) 0 D) 1

B)

To investigate the relationship between yield of soybeans and the amount of fertilizer used, a researcher divides a field into eight plots of equal size and applies a different amount of fertilizer to each plot. The table shows the yield of soybeans and the amount of fertilizer used for each plot. Amount of fertilizer (pounds) ,x 1 1.5 2 2.5 3 3.5 4 4.5 Yield of soybeans (pounds), y 25 21 27 28 36 35 32 34 A) r = 0.683; no linear relation exists B) r = 0.819; linear relation exists C) r = 0.683; linear relation exists D) r = 0.729; no linear relation exists

B)

Use the spinner below to answer the question. Assume that it is equally probable that the pointer will land on any one of the five numbered spaces. If the pointer lands on a borderline, spin again. Find the probability that the arrow will land on an odd number. A) 2/5 B) 3/5 C) 0 D) 1

B)

Which measure of central tendency is more representative of the typical observation if the graph of the data is skewed to the left? A) Mean B) Median C) Mode D) Midrange

B)

he table below shows the scores on an end-of-year project of 10 randomly selected architecture students and the number of days each student spent working on the project. A) r = 0.761; linear relation exists B) r = 0.847; linear relation exists C) r = 0.847; no linear relation exists D) r = 0.761; no linear relation exists

B)

the speed of a car on a New York tollway during rush hour traffic A) discrete B) continuous

B)

Who got the fewest votes? A) Jim B) Ming C) Ann D) Ted

B) Ming

A writer for an art magazine randomly selects and interviews fifty male and fifty female artists. What sampling technique is used? A) convenience B) stratified C) simple random D) cluster E) systematic

B) stratified

The data below are the average one-way commute times (in minutes) for selected students and the number of absences for those students during the term. Find the equation of the regression line for the given data. What would be the predicted number of absences if the commute time was 40 minutes? Is this a reasonable question? Round the predicted number of absences to the nearest whole number. Round the regression line values to the nearest hundredth. A) y= 0.45x - 30.27; -12 absences; Yes, it is reasonable. B) y= 0.45x + 30.27; 48 absences; Yes, it is reasonable. C) y= 0.45x - 30.27; -12 absences; No, it is not reasonable. 40 minutes is well outside the scope of the model. D) y= 0.45x + 30.27; 48 absences; No, it is not reasonable. 40 minutes is well outside the scope of the model.

C)

The data below are the final exam scores of 10 randomly selected history students and the number of hours they slept the night before the exam. Find the equation of the regression line for the given data. What would be the predicted score for a history student who slept 7 hours the previous night? Is this a reasonable question? Round the regression line values to the nearest hundredth, and round the predicted score to the nearest whole number. A) y= -5.04x + 56.11; 21; Yes, it is reasonable. B) y= 5.04x + 56.11; 91; No, it is not reasonable. 7 hours is well outside the scope of the model. C) y= 5.04x + 56.11; 91; Yes, it is reasonable. D) y= -5.04x + 56.11; 21; No, it is not reasonable. 7 hours is well outside the scope of the model

C)

The data below are the number of absences and the final grades of 9 randomly selected students from a literature class. Find the equation of the regression line for the given data. What would be the predicted final grade if a student was absent 14 times? Round the regression line values to the nearest hundredth. Round the predicted grade to the nearest whole number. A) y ^ = 96.14x - 2.75; 1343 B) y ^ = -96.14x + 2.75; 1343 C) y ^ = -2.75x + 96.14; 58 D) y ^ = -2.75x - 96.14; 134.64

C)

The distribution of Bachelor's degrees conferred by a university is listed in the table. Assume that a student majors in only one subject. What is the probability that a randomly selected student with a Bachelor's degree majored in Physics or Philosophy? Round your answer to three decimal places. Major Frequency Physics 228 Philosophy 208 Engineering 86 Business 176 Chemistry 222 A) 0.526 B) 0.226 C) 0.474 D) 0.248

C)

The following data are the yields, in bushels, of hay from a farmer's last 10 years: 375, 210, 150, 147, 429, 189, 320, 580, 407, 180. Find the IQR. A) 265 B) 279 C) 227 D) 253

C)

The following data represent a random sample of 15 complaints registered with the customer service department of a store. Determine the mode complaint. messy store other rude personnel excessive waiting time |messy store| messy store| excessive waiting time| defective product |excessive waiting time| messy store |excessive waiting time| excessive waiting time| other |messy store| excessive waiting time| A) rude personnel B) messy store C) excessive waiting time D) no mode

C)

The heights of ten female students (in inches) in a college math class are listed below. Find the mean. 65 66 67 66 67 70 67 70 71 68 A) 65.5 inches B) 71.1 inches C) 67.7 inches D) 70.0 inches

C)

The manager of a used car lot took inventory of the automobiles on his lot and constructed the following table based on the age of his car and its make (foreign or domestic). A car was randomly selected from the lot. Given that the car selected was a foreign car, what is the probability that it was older than 2 years? Age of Car (in years) A) 42/113 B) 58/113 C) 29/50 D) 21/50

C)

The manager of a used car lot took inventory of the automobiles on his lot and constructed the following table based on the age of his car and its make (foreign or domestic). A car was randomly selected from the lot. Given that the car selected was a domestic car, what is the probability that it was older than 2 years? A) 21/50 B) 10/21 C) 3/5 D) 1 /5

C)

The managers of a corporation were surveyed to determine the background that leads to a successful manager. Each manager was rated as being either a good, fair, or poor manager by his/her boss. The manager's educational background was also noted. The data appear below. Given that a manager is a good manager, what is the probability that this manager has some college background? A) 1/32 B) 5/18 C) 5/39 D) 8/13

C)

The number of students enrolled in a physics class for the last ten semesters are listed below. Find the median number of students. 65 66 67 66 67 70 67 70 71 68 A) 66 students B) 68 students C) 67 students D) 70 students

C)

The probability that a football game will go into overtime is 10%. In 80 randomly selected football games, what is the mean and the standard deviation of the number that went into overtime? A) mean: 8; standard deviation: 2.82842712 B) mean: 7.2; standard deviation: 2.68328157 C) mean: 8; standard deviation: 2.68328157 D) mean: 7.2; standard deviation: 2.82842712

C)

The regression line for the given data is y ^ = 2.097x - 0.552. Determine the residual of a data point for which x =-2 and y = -6. A) 11.134 B) -10.746 C) -1.254 D) -4.746

C)

Use the following frequency distribution to determine the class limits of the third class. Class Frequency 9-15 5 16-22 9 23-29 6 30-36 3 37-43 7 44-50 4 A) lower limit: 22; upper limit: 30 B) lower limit: 23; upper limit: 30 C) lower limit: 23; upper limit: 29 D) lower limit: 22.5; upper limit: 29.5

C)

What is the difference between a bar chart and a histogram? A) There is no difference between these two graphical displays. B) The bars in a bar chart are all the same width while the bars of a histogram may be of various widths. C) The bars on a bar chart do not touch while the bars of a histogram do touch. D) The bars in a bar chart may be of various widths while the bars of a histogram are all the same width.

C)

What percent of the votes did Ted and Gina receive together? A) 59% B) 19% C) 41% D) 22%

C)

__________ is a condition applied to the experimental units involved in an experiment. A) The factor level B) The sampling design C) A treatment D) The design

C)

In a recent online survey, participants were asked to answer "yes" or "no" to the question "Are you in favor of stricter gun control?" 6571 responded "yes" while 4537 responded "no". There was a fifty-cent charge for the call. What sampling technique was used? A) simple random B) systematic C) convenience D) stratified

C) convenience

The class width is the

difference between consecutive lower class limits. The class width of the data given above is 35 − 25 = 10

The interquartile range, IQR, is the range of the

middle 50% of the observations in a data set. That is, the IQR is the difference between the third and first quartiles and is found using the formula

A double-blind experiment is one in which

neither the experimental unit nor the researcher in contact with the experimental unit knows which treatment the experimental unit is receiving.

The population standard deviation of a variable is the

square root of the sum of squared deviations about the population mean divided by the number of observations in the population, N. That is, it is the square root of the mean of the squared deviations about the population mean.The population standard deviation is symbolically represented by σ (lowercase Greek sigm

The z-score represents

the distance that a data value is from the mean in terms of the number of standard deviations. We find it by subtracting the mean from the data value and dividing this result by the standard deviation

) In order for a company's employees to work in a foreign office, they must take a test in the language of the country where they plan to work. The data below shows the relationship between the number of years that employees have studied a particular language and the grades they received on the proficiency exam. Calculate the linear correlation coefficient. A.0.902 B) 0.891 C) 0.934 D) 0.911

C)

) The following data represent the living situation of newlyweds in a large metropolitan area and their annual household income. What percent of people who live with family make between $35,000 and $50,000 per year? Round to the nearest tenth of a percent A) 2.1% B) 35.6% C) 15.5% D) 10.6%

C)

A drug company wanted to test a new acne medication. The researchers found 400 adults aged 25-35 and randomly assigned them to two groups. The first group received the new drug, while the second received a placebo. After one month of treatment, the percentage of each group whose acne symptoms decreased was recorded and compared. Identify the experimental units. A) the drug (medication or placebo) B) the percentage who had decreased acne symptoms C) the 400 adults aged 25-35 D) the one month treatment time

C)

A fair coin is tossed two times in succession. The set of equally likely outcomes is {HH, HT, TH, TT}. Find the probability of getting the same outcome on each toss. A) 1 B) 3/4 C) 1/2 D) 1/4

C)

A farmer wishes to test the effects of a new fertilizer on her soybean yield. She has four equal-sized plots of land-- one with sandy soil, one with rocky soil, one with clay-rich soil, and one with average soil. She divides each of the four plots into three equal-sized portions and randomly labels them A, B, and C. The four A portions of land are treated with her old fertilizer. The four B portions are treated with the new fertilizer, and the four C's are treated with no fertilizer. At harvest time, the soybean yield is recorded for each section of land. What is the response variable in this experiment? A) the type of fertilizer (old, new, or none) B) the section of land (A, B, or C) C) the soybean yield recorded for each section of land D) the four types of soil

C)

A farmer wishes to test the effects of a new fertilizer on her wheat yield. She has four equal-sized plots of land-- one with sandy soil, one with rocky soil, one with clay-rich soil, and one with average soil. She divides each of the four plots into three equal-sized portions and randomly labels them A, B, and C. The four A portions of land are treated with her old fertilizer. The four B portions are treated with the new fertilizer, and the four C's are treated with no fertilizer. At harvest time, the wheat yield is recorded for each section of land. How many levels does the treatment have in this experiment? A) 1 (wheat yield) B) 12 (sections of land) C) 3 (old, new, or no fertilizer) D) 4 (rocky, sandy, clay, or average soil)

C)

A local country club has a membership of 600 and operates facilities that include an 18-hole championship golf course and 12 tennis courts. Before deciding whether to accept new members, the club president would like to know how many members regularly use each facility. A survey of the membership indicates that 69% regularly use the golf course, 41% regularly use the tennis courts, and 4% use neither of these facilities regularly. Given that a randomly selected member uses the tennis courts regularly, find the probability that they also use the golf course regularly. A) 0.146 B) 0.203 C) 0.341 D) 0.127

C)

A manager wishes to determine the relationship between the number of years the manager's sales representatives have been with the company and their average monthly sales (in thousands of dollars). Calculate the linear correlation coefficient. A) 0.717 B) 0.561 C) 0.632 D) 0.791

C)

A medical journal published the results of an experiment on anxiety. The experiment investigated the effects of a controversial new therapy for anxiety. Researchers measured the anxiety levels of 31 adult women who suffer moderate conditions of the disorder. After the therapy, the researchers again measured the women's anxiety levels. The differences between the the pre- and post-therapy anxiety levels were reported. What is the response variable in this experiment? A) the therapy B) the 31 adult women who suffer from anxiety C) the differences between the the pre- and post-therapy anxiety levels D) the disorder (anxiety or no anxiety)

C)

A medical journal published the results of an experiment on insomnia. The experiment investigated the effects of a controversial new therapy for insomnia. Researchers measured the insomnia levels of 33 adult women who suffer moderate conditions of the disorder. After the therapy, the researchers again measured the women's insomnia levels. The differences between the the pre- and post-therapy insomnia levels were reported. What is the treatment in this experiment? A) the 33 adult women who suffer from insomnia B) the disorder (insomnia or no insomnia) C) the therapy D) the differences between the the pre- and post-therapy insomnia levels

C)

A numerical summary of a population is a A) Qualitative response B) Variable C) Parameter D) Statistic

C)

A random sample of sale prices of homes yielded the following summary information: MIN $46,000 25%: $81,000 Median: $136,000 MAX $272,000 75%: $164,000 Comment on a home that had a sale price of $411,000. A) This sale price would be expected since it falls inside the lower and upper fences. B) This sale price falls between the lower and upper fences. It can be considered a potential outlier. C) This value falls outside the upper fence and is considered an outlier. D) This value falls outside of the third quartile, but cannot be considered an outlier.

C)

A recent article in the paper claims that government ethics are at an all-time low. Reporting on a recent sample, the paper claims that 39% of all constituents believe their representative possesses low ethical standards. Assume that responses were randomly and independently collected. A representative of a district with 1,000 people does not believe the paper's claim applies to her. If the claim is true, how many of the representative's constituents believe the representative possesses low ethical standards? A) 961 B) 610 C) 390 D) 39

C)

A recent survey found that 73% of all adults over 50 wear sunglasses for driving. In a random sample of 20 adults over 50, what is the mean and standard deviation of those that wear sunglasses? A) mean: 5.4; standard deviation: 1.98544705 B) mean: 5.4; standard deviation: 3.82099463 C) mean: 14.6; standard deviation: 1.98544705 D) mean: 14.6; standard deviation: 3.82099463

C)

A single die is rolled twice. The set of 36 equally likely outcomes is {(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6), (2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6), (3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6), (4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (4, 6), (5, 1), (5, 2), (5, 3), (5, 4), (5, 5), (5, 6), (6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)}. Find the probability of getting two numbers whose sum is less than 13. A) 1/4 B) 1/2 C) 1 D) 0

C)

A study was designed to investigate the effects of two variables - (1) a student's level of mathematical anxiety and (2) teaching method - on a student's achievement in a mathematics course. Students who had a low level of mathematical anxiety were taught using the traditional expository method. These students obtained a mean score of 340 with a standard deviation of 50 on a standardized test. Assuming a bell-shaped distribution, where would approximately 95% of the students score? A) below 190 or above 490 B) below 240 or above 440 C) between 240 and 440 D) between 190 and 490

C)

According to insurance records a car with a certain protection system will be recovered 94% of the time. Find the probability that 3 of 6 stolen cars will be recovered. A) 0.94 B) 0.06 C) 0.004 D) 0.500

C)

An experiment in which neither the experimental unit nor the researcher in contact with the experimental unit knows which treatment the experimental unit is receiving is called a ________________ . A) single-blind experiment B) randomized block design C) double-blind experiment D) matched-pairs design

C)

An unusual event is an event that has a A) Probability which exceeds 1 B) Probability of 1 C) Low probability of occurrence D) A negative probability

C)

Assume that it is equally probable that the pointer will land on any one of the five numbered spaces. If the pointer lands on a borderline, spin again. Find the probability that the arrow will land on 3 or 1. A) 1 B) 1/ 3 C) 2/ 5 D) 3

C)

Calculate the linear correlation coefficient for the data below. A) 0.881 B) 0.792 C) 0.990 D) 0.819

C)

Classify the statement as an example of classical probability, empirical probability, or subjective probability. The probability that it will snow tomorrow is 84%. A) empirical probability B) classical probability C) subjective probability

C)

Each year advertisers spend billions of dollars purchasing commercial time on network sports television. In the first 6 months of 1988, advertisers spent $1.1 billion. A recent article listed the top 10 leading spenders (in millions of dollars): Company A $70 Company F $26.3 Company B 61.3 Company G 26.1 Company C 57.5 Company H 22.5 Company D 56.3 Company I 22.1 Company E 28.7 Company J 19.7 Calculate the mean amount spent. A) 384.88 million dollars B) 19.62 million dollars C) 39.05 million dollars D) 50.30 million dollars

C)

Each year advertisers spend billions of dollars purchasing commercial time on network sports television. In the first 6 months of the year, advertisers spent $1.1 billion. A recent article listed the top 10 leading spenders (in millions of dollars): Company A $72.8 Company F $27.1 Company B 60.7 Company G 27 Company C 57.9 Company H 23.7 Company D 54.7 Company I 23.4 Company E 31.1 Company J 20.9 Calculate the median. A) 5.39 million dollars B) 51.90 million dollars C) 29.10 million dollars D) 39.93 million dollars

C)

Find the equation of the regression line for the given data. Round values to the nearest thousandth. A) y= -2.097x + 0.206 B) y= 0.206x - 2.097 C) y= -0.206x + 2.097 D)y= 2.097x - 0.206

C)

Given that P(A or B) = 1 2 , P(A) = 1 5 , and P(A and B) = 1 8 , find P(B). Express the probability as a simplified fraction. A) 33 /40 B) 3/ 16 C) 17 /40 D) 23 /40

C)

If one card is drawn from a standard 52 card playing deck, determine the probability of getting a ten, a king or a diamond. Round to the nearest hundredth. A) 0.40 B) 0.31 C) 0.37 D) 0.29

C)

If p is the probability of success of a binomial experiment, then the probability of failure is A) x/n B) n/x C) 1 - p D) -p

C)

If two events have no outcomes in common they are said to be A) At odds B) Conditional C) Disjoint D) Independent

C)

In an area of the Great Plains, records were kept on the relationship between the rainfall (in inches) and the yIn an area of the Great Plains, records were kept on the relationship between the rainfall (in inches) and the yield of wheat (bushels per acre). Calculate the linear correlation coefficient. A) 0.900 B) 0.899 C) 0.981 D) 0.998

C)

In the game of roulette in the United States a wheel has 38 slots: 18 slots are black, 18 slots are red, and 2 slots are green. We watched a friend play roulette for two hours. In that time we noted that the wheel was spun 50 times and that out of those 50 spins black came up 22 times. Based on this data, the P(black ) = 22 50 = 0.44. This is an example of what type of probability? A) Subjective B) Classical C) Empirical D) Observational

C)

Make a scatter diagram for the data. Use the scatter diagram to describe how, if at all, the variables are related. Subject A B C D E F G x Time watching TV 13 9 7 12 12 10 11 y Time on Internet 14 12 8 17 18 9 18

C)

Use the regression equation to predict the value of y for x = -3.5. A) 7.356 B) -0.768 C) -4.538 D) -5.839

A)

category of storm (gale, hurricane, etc.) A) ordinal B) interval C) nominal D) ratio

A) ordinal

The commuting times of ten employees (in minutes) are listed below. Find the mode score. 65 66 67 66 67 70 67 70 71 68 A) 66 minutes B) 67 minutes C) 65 minutes D) 68 minutes

B)

The data below are the final exam scores of 10 randomly selected statistics students and the number of hours they slept the night before the exam. Compute the sum of the squared residuals of the least-squares line for the given data. A) 1122.1 B) 318.038 C) 39.755 D) 804.062

B)

The data below are the number of absences and the salaries (in thousands of dollars) of 9 randomly selected employees from an engineering firm. What is the best predicted value for y given x = 12? A) 65 B) 63 C) 64 D) 62

B)

A probability experiment is conducted in which the sample space of the experiment is S = {5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}. Let event A = {8, 9, 10, 11, 12}. Assume that each outcome is equally likely. List the outcomes in Ac. Find P(Ac). A) {13, 14, 15}; 3/11 B) {5, 6, 7, 12, 13, 14, 15}; 7/11 C) {5, 6, 7, 13, 14, 15}; 6/11 D) {8, 9, 10, 11, 12}; 5/11

C)

Assume that male and female births are equally likely and that the birth of any child does not affect the probability of the gender of any other children. Find the probability of exactly five girls in ten births. A) 7.875 B) 0.05 C) 0.246 D) 0.5

C)

Classify the statement as an example of classical probability, empirical probability, or subjective probability. It is known that the probability of hitting a pothole while driving on a certain road is 1%. A) classical probability B) subjective probability C) empirical probability

C)

Fill in the blank. The _________ of an event A is the event that A does not occur. A) Venn diagram B) intersection C) complement D) union

C)

In interpreting a boxplot of a data set we note that the median is to the left of the center of the box and the right line is longer than the left line. We can conclude that A) The data is symmetric. B) The data is skewed left. C) The data is skewed right. D) Skewness or symmetry cannot be determined by a box plot.

C)

In which scatter diagram is r = 1? A) f B) d C) b D) a

C)

The following data represent the bachelor degrees of CEO's at area small businesses. Determine the mode degree. Degree Number Accounting 21 Business 49 Liberal Arts 5 Marketing 27 Other 6 A) marketing B) no mode C) business D) accounting

C)

Use the regression equation to predict the value of y for x = -4.2. A) -8.255 B) 4.415 C) -9.359 D) -0.221

C)

The United States can be divided into four geographical regions: Northeast, South, Midwest, and West. The Northeast region consists of 9 states; the South region consists of 16 states; the Midwest consists of 12 states; and the West consists of 13 states. If a survey is to be administered to the governors of 10 of the states and we want equal representation for the states in each of the four regions, how many states from the South should be selected? Round to the nearest whole state. A) 4 B) 2 C) 3 D) 5

C)

The average score of local students on a college entrance exam is 110, with a standard deviation of 5. The distribution is roughly bell shaped. Use the Empirical Rule to find the percentage of local students with scores above 120. A) 95% B) 5% C) 2.5% D) 97.5%

C)

The boxplot shown below was constructed in Excel for the amount of soda that was poured by a filling machine into 12-ounce soda cans at a local bottling company. Based on the information given in the boxplot below, what shape do you believe the data to have? A) skewed to the right B) approximately symmetric C) skewed to the left D) cannot be determined

C)

The breakdown of workers in a particular state according to their political affiliation and type of job held is shown here. Suppose a worker is selected at random within the state and the worker's political affiliation and type of job are noted. Given the worker is a Democrat, what is the probability that the worker is in a white collar job A) 0.423 B) 0.456 C) 0.262 D) 0.193

C)

The class width is the difference between A) The upper class limit and the lower class limit of a class B) The largest frequency and the smallest frequency C) Two successive lower class limits D) The high and the low data values

C)

The commute times (in minutes) of 30 employees are listed below. Find Q3. 31 41 45 48 52 55 56 56 63 65 67 67 69 70 70 74 75 78 79 79 80 81 83 85 85 87 90 92 95 99 A) 56 min B) 72 min C) 83 min D) 82 min

C)

The complement of 4 heads in the toss of 4 coins is A) All tails B) Exactly one tail C) At least one tail D) Three heads

C)

A calculus instructor is interested the performance of his students from Calculus I that go on to Calculus II. Their final grades in each course (in percent) are given below. Compute the sum of the squared residuals of the least squared line for the given data A) 1075.9 B) 11.41 C) 30.85 D) 130.14

D)

A die is rolled. The set of equally likely outcomes is {1, 2, 3, 4, 5, 6}. Find the probability of getting a 3. A) 1/2 B) 0 C) 3 D) 1/6

D)

A researcher determines that the linear correlation coefficient is 0.85 for a paired data set. This indicates that there is A) no linear correlation but that there may be some other relationship. B) a strong negative linear correlation. C) insufficient evidence to make any decision about the correlation of the data. D) a strong positive linear correlation.

D)

In which scatter diagram is r = 0.01? A) f B) d C) c D) e

D)

The names of 40 employees are written on 40 cards. The cards are placed in a bag, and three names are picked from the bag. What sampling technique was used? A) cluster B) convenience C) systematic D) simple random E) stratified

D) simple random

residual for a point

The difference between the observed value of y and the predicted value of y is the error,

A bag contains 25 wooden beads. The colors of the beads are red, blue, white, green, black, brown, and grey. The probability of randomly selecting a bead of a particular color from the bag is given below. Is this a probability model? Answer yes or No. A) Yes B) No

B)

A baseball player is asked to swing at pitches in sets of four. The player swings at 100 sets of 4 pitches. The probability distribution for hitting a particular number of pitches is given below. Determine the standard deviation for this discrete probability distribution. x 0 1 2 3 4 P(x) 0.02 0.07 0.22 0.27 0.42 A) 1.10 B) 1.05 C) 0.28 D) 1.21

B)

A card is drawn from a standard deck of 52 playing cards. Find the probability that the card is a queen or a club. Express the probability as a simplified fraction. A) 3/13 B) 4/13 C) 7/52 D) 2/13

B)

A dice game involves throwing three dice and betting on one of the six numbers that are on the dice. The game costs $11 to play, and you win if the number you bet appears on any of the dice. The distribution for the outcomes of the game (including the profit) is shown below: Find your expected profit from playing this game. A) $11.20 B) -$1.53 C) $5.96 D) $0.50

B)

A group of 79 students were asked how far they commute to work from home each time they go to work from home. The results are given below. Determine the first quartile. Miles traveled Frequency 1 1 2 2 3 12 4 18 5 7 6 10 7 10 8 11 9 5 10 3 A) 5 mi B) 4 mi C) 6 mi D) 3 mi

B)

A group of 79 students were asked how far they commute to work from home each time they go to work from home. The results are given below. Would a drive of 15 miles be considered an outlier? Answer Yes or No. Miles traveled Frequency 1 1 2 2 3 12 4 18 5 7 6 10 7 10 8 11 9 5 10 3 A) No B) Yes

B)

A highly selective boarding school will only admit students who place at least 1.5 z-scores above the mean on a standardized test that has a mean of 110 and a standard deviation of 12. What is the minimum score that an applicant must make on the test to be accepted? A) 92 B) 128 C) 122 D) 98

B)

A local bakery has determined a probability distribution for the number of cheesecakes that they sell in a given day. The distribution is as follows: Number sold in a day 0 5 10 15 20 Prob (Number sold) 0.08 0.05 0.25 0.22 0.4 Find the number of cheesecakes that this local bakery expects to sell in a day. A) 14.13 B) 14.05 C) 14.45 D) 10

B)

A manager asked her employees how many times they had given blood in the last year. The results of the survey are given below. The random variable x represents the number of times a person gave blood and P(x) represents the probability of selecting an employee who had given blood that percent of the time. What is the mean number of times a person gave blood based on this survey? x 0 1 2 3 4 5 6 P(x) 0.30 0.25 0.20 0.12 0.07 0.04 0.02 A) 3.0 B) 1.6 C) 2.0 D) 0.14

B)

A manager at a local company asked his employees how many times they had given blood in the last year. The results of the survey are given below. The random variable x represents the number of times a person gave blood and P(x) represents the probability of selecting an employee who had given blood that percent of the time. What is the standard deviation for the number of times a person gave blood based on this survey? A) 1.16 B) 1.54 C) 1.82 D) 2.23

B)

A medical journal published the results of an experiment on anorexia. The experiment investigated the effects of a controversial new therapy for anorexia. Researchers measured the anorexia levels of 84 adult women who suffer moderate conditions of the disorder. After the therapy, the researchers again measured the women's anorexia levels. The differences between the the pre- and post-therapy anorexia levels were reported. What type of experimental design is this? A) completely randomized design B) matched-pairs design C) randomized block design D) single-blind design

B)

A medical researcher wishes to determine if there is a relationship between the number of prescriptions written by pediatricians and the ages of the children for whom the prescriptions are written. She surveys all the pediatricians in a geographical region to collect her data. What is the response variable? A) Pediatricians surveyed B) Number of prescriptions written C) Number of children for whom prescriptions were written D) Age of the children for whom prescriptions were written

B)

A quiz consists of 20 true or false questions. If the student guesses on each question, what is the standard deviation of the number of correct answers? A) 3.16227766 B) 2.23606798 C) 0 D) 2

B)

A researcher records the number of employees of each of the IT companies in the town of Westmoore. The results are summarized in the table. Number of Employees Number of IT Companies 0 - 749 34 750 - 1499 24 1500 - 2249 9 2250 - 2999 7 3000 - 3749 5 Find the class width. A) 749.5 B) 750 C) 3749 D) 5

B)

A seed company has a test plot in which it is testing the germination of a hybrid seed. They plant 50 rows of 40 seeds per row. After a two-week period, the researchers count how many seed per row have sprouted. They noted that least number of seeds to germinate was 33 and some rows had all 40 germinate. The germination data is given below in the table. The random variable x represents the number of seed in a row that germinated and P(x) represents the probability of selecting a row with that number of seed germinating. Determine the standard deviation of the number of seeds per row that germinated. A) 7.13 B) 1.51 C) 36.86 D) 6.07

B)

A small computing center has found that the number of jobs submitted per day to its computers has a distribution that is approximately bell shaped, with a mean of 76 jobs and a standard deviation of 7. Where do we expect most (approximately 95%) of the distribution to fall? A) between 62 and 97 jobs per day B) between 62 and 90 jobs per day C) between 55 and 97 jobs per day D) between 69 and 83 jobs per day

B)

A traffic officer is compiling information about the relationship between the hour or the day and the speed over the limit at which the motorist is ticketed. He computes a correlation coefficient of 0.12. What does this tell the officer? A) There is a moderate positive linear correlation. B) There is a weak positive linear correlation. C) There is a moderate negative linear correlation. D) There is insufficient evidence to make any conclusions about the relationship between the variables.

B)

According to the Federal Communications Commission, 70% of all U.S. households have vcrs. In a random sample of 15 households, what is the probability that the number of households with vcrs is between 10 and 12, inclusive? A) 0.4053 B) 0.5947 C) 0.7 D) 0.2061

B)

After completing an inventory of three warehouses, a golf club shaft manufacturer described its stock of 12,246 shafts with the percentages given in the table. Suppose a shaft is selected at random from the 12,246 currently in stock, and the warehouse number and type of shaft are observed. Find the probability that the shaft was produced in a warehouse other than warehouse 1. Round the the nearest hundredth. A) 0.43 B) 0.65 C) 0.35 D) 0.82

B)

An experiment in which the experimental unit (or subject) does not know which treatment he or she is receiving is called a ________________ . A) randomized block design B) single-blind experiment C) matched-pairs design D) double-blind experiment

B)

At a tennis tournament a statistician keeps track of every serve. The statistician reported that the mean serve speed of a particular player was 103 miles per hour (mph) and the standard deviation of the serve speeds was 14 mph. Assume that the statistician also gave us the information that the distribution of the serve speeds was bell shaped. What proportion of the player's serves are expected to be between 131 mph and 145 mph? A) 0.95 B) 0.0235 C) 0.047 D) 0.997

B)

Choose the coefficient of determination that matches the scatterplot. Assume that the scales on the horizontal and vertical axes are the same. A) R2 = 0.82 B) R2 = 0.43 C) R2 = 0.12 D) R2 = -0.43

B)

Eleven high school teachers were asked to give the number of students in their classes. The sample data follows. Would any of the class sizes be considered an outlier? Answer Yes or No. 36, 31, 30, 31, 20, 19, 24, 34, 21, 28, 24 A) Yes B) No

B)

Find the class width for the frequency table below. Class Frequency 22-23 3 24-25 1 26-27 3 28-29 6 30-31 2 A) 1 B) 2 C) 1.5 D) 2.5

B)

Find the population mean or sample mean as indicated. Population: 6, 10, 2, 11, 14, 5 A) μ = 11 B) μ = 8 C) -x = 9 D) -x = 10

B)

Given the following five-number summary, find the IQR. 2.9, 5.7, 10.0, 13.2, 21.1. A) 18.2 B) 7.5 C) 11.1 D) 7.1

B)

Given the table of probabilities for the random variable x, does this form a probability distribution? Answer Yes or No A) Yes B) No

B)

Health care issues are receiving much attention in both academic and political arenas. A sociologist recently conducted a survey of citizens over 60 years of age whose net worth is too high to qualify for government health care but who have no private health insurance. The ages of 25 uninsured senior citizens were as follows: 68 73 66 76 86 74 61 89 65 90 69 92 76 62 81 63 68 81 70 73 60 87 75 64 82 Suppose the mean and standard deviation are 74.0 and 9.7, respectively. If we assume that the distribution of ages is bell shaped, what percentage of the respondents will be between 64.3 and 93.4 years old? A) approximately 83.9% B) approximately 81.5% C) approximately 68% D) approximately 95%

B)

In terms of probability, a(n) ___________________ is any process with uncertain results that can be repeated. A) Outcome B) Experiment C) Event D) Sample space

B)

Select a random sample of five state capitals from the list below using the two digit list of random numbers provided. Begin with the uppermost left random number and proceed down each column. When a column is complete, use the numbers at the top of the next right column and proceed down that column. State Capitals A) Boston, MA; Concord, NH; Dover DE; Santa Fe, NM; Richmond, VA. B) Springfield, IL; Atlanta,GA; Providence, RI; Santa Fe, NM; Columbus OH. C) Springfield, IL; Des Moines, IA; Boston, MA; Santa Fe, NM; Columbus OH. D) Carson City NV; Boise ID; Atlanta, GA; Cheyenne, WY; Boston, MA.

B)

The ______________ probability of an outcome is a probability based on personal judgment. A) Empirical B) Subjective C) Classical D) Conditional

B)

The amount of television viewed by today's youth is of primary concern to Parents Against Watching Television (PAWT). 300 parents of elementary school-aged children were asked to estimate the number of hours per week that their child watched television. The mean and the standard deviation for their responses were 14 and 4, respectively. PAWT constructed a stem-and-leaf display for the data that showed that the distribution of times was a bell-shaped distribution. Give an interval around the mean where you believe most (approximately 95%) of the television viewing times fell in the distribution. A) less than 10 and more than 18 hours per week B) between 6 and 22 hours per week C) between 10 and 18 hours per week D) between 2 and 26 hours per week

B)

The data below are ages and systolic blood pressures (measured in millimeters of mercury) of 9 randomly selected adults. Find the equation of the regression line for the given data. What would be the predicted pressure if the age was 60? Round the predicted pressure to the nearest whole number. Round the regression line values to the nearest hundredth. A) y ^ = 60.46x - 1.49; 3626 mm B) y ^ = 1.49x + 60.46; 150 mm C) y ^ = 1.49x - 60.46; 29 mm D) y ^ = 60.46x + 1.49; 3629 mm

B)

The data below are the number of hours worked (per week) and the final grades of 9 randomly selected students from a drama class. Calculate the linear correlation coefficient. A) -0.899 B) -0.991 C) -0.918 D) -0.888

B)

The data below are the temperatures on randomly chosen days during the summer in one city and the number of employee absences on those days for a company located in the same city. What is the best predicted value for y given x = 74? A) 5 B) 3 C) 6 D) 4

B)

) In an area of the Great Plains, records were kept on the relationship between the rainfall (in inches) and the yield of wheat (bushels per acre). Compute the sum of the squared residuals of the least-squares line for the given data. Rain fall (in inches), A) 2207.628 B) 4.379 C) 0 D) 87.192

D)

) The below table shows the probabilities generated by rolling one die 50 times and noting the up face. What is the probability of getting an odd up face and a two or less? Round the the nearest hundredth. Roll 1 2 3 4 5 6 Probability 0.22 0.10 0.18 0.12 0.18 0.20 A) 0.66 B) 0.32 C) 0.90 D) 0.68

D)

) The median of a data set for a variable is the data value that A) Appears the most often B) Is the average, that is, the sum of all the data values of the variable divided by the number of observations in the data set? C) None of these D) Lies in the middle of the data when the data is arranged in ascending order.

D)

A drug company wanted to test a new indigestion medication. The researchers found 600 adults aged 25-35 and randomly assigned them to two groups. The first group received the new drug, while the second received a placebo. After one month of treatment, the percentage of each group whose indigestion symptoms decreased was recorded and compared. What is the response variable in this experiment? A) the type of drug (medication or placebo) B) the one month treatment time C) the 600 adults aged 25-35 D) the percentage who had decreased indigestion symptoms

D)

A fast-food restaurant chain with 700 outlets in the United States describes the geographic location of its restaurants with the accompanying table of percentages. A restaurant is to be chosen at random from the 700 to test market a new style of chicken. Given that the restaurant is located in the eastern United States, what is the probability it is located in a city with a population of at least 10,000? A) 0.43 B) 0.483 C) 0.157 D) 0.843

D)

A history instructor has given the same pretest and the same final examination each semester. He is interested in determining if there is a relationship between the scores of the two tests. He computes the linear correlation coefficient and notes that it is 1.15. What does this correlation coefficient value tell the instructor? A) The correlation is something other than linear. B) There is a strong positive correlation between the tests. C) There is a strong negative correlation between the tests. D) The history instructor has made a computational error.

D)

A local country club has a membership of 600 and operates facilities that include an 18-hole championship golf course and 12 tennis courts. Before deciding whether to accept new members, the club president would like to know how many members regularly use each facility. A survey of the membership indicates that 60% regularly use the golf course, 47% regularly use the tennis courts, and 8% use neither of these facilities regularly. What percentage of the 600 use at least one of the golf or tennis facilities? A) 99% B) 15% C) 8% D) 92%

D)

A recent article in the paper claims that government ethics are at an all-time low. Reporting on a recent sample, the paper claims that 34% of all constituents believe their representative possesses low ethical standards. Suppose 20 of a representative's constituents are randomly and independently sampled. Assuming the paper's claim is correct, find the probability that more than eight but fewer than 12 of the 20 constituents sampled believe their representative possesses low ethical standards. A) 0.261917 B) 0.357678 C) 0.133574 D) 0.193391

D)

A salesman boasts to a farmer that his new fertilizer will increase the yield of the farmer's crops by 15%. The farmer wishes to test the effects of the new fertilizer on her corn yield. She has four equal sized plots of land one with sandy soil, one with rocky soil, one with clay-rich soil, and one with average soil. She divides each of the four plots into three equal sized portions and randomly labels them A, B and C. The four A portions are treated with her old fertilizer. The four B portions are treated with the new fertilizer. The four C portions receive no fertilizer. At harvest time, the corn yield is recorded for each section of land. What is the claim she is testing? A) The average soil field had at least a 15% increase in yield. B) The A sections had at least a 15% increase in yield. C) The total yield increased at least 15%. D) The new fertilizer yielded at least a 15% improvement.

D)

A scatter diagram locates a point in a two dimensional plane. The diagram locates the variable on the horizontal axis and the variable on the vertical axis. A) study; explanatory B) response; explanatory C) response; study D) explanatory; response

D)

A seed company has a test plot in which it is testing the germination of a hybrid seed. They plant 50 rows of 40 seeds per row. After a two-week period, the researchers count how many seed per row have sprouted. They noted that least number of seeds to germinate was 33 and some rows had all 40 germinate. The germination data is given below in the table. The random variable x represents the number of seed in a row that germinated and P(x) represents the probability of selecting a row with that number of seed germinating. Determine the mean number of seeds per row that germinated A) 36 B) 36.5 C) 0.13 D) 36.9

D)

A severe drought affected several western states for 3 years. A Christmas tree farmer is worried about the drought's effect on the size of his trees. To decide whether the growth of the trees has been retarded, the farmer decides to take a sample of the heights of 25 trees. Typically trees of this age have a mean height of 65 inches with a standard deviation of 9 inches. Assuming the distribution is bell shaped, where do you expect middle 95% of the tree heights to fall? A) over 56 inches tall B) between 38 and 92 inches tall C) between 56 and 74 inches tall D) between 47 and 83 inches tall

D)

A study was designed to investigate the effects of two variables - (1) a student's level of mathematical anxiety and (2) teaching method - on a student's achievement in a mathematics course. Students who had a low level of mathematical anxiety were taught using the traditional expository method. These students obtained a mean score of 400 with a standard deviation of 40 on a standardized test. Assuming no information concerning the shape of the distribution is known, what percentage of the students scored between 320 and 480? A) approximately 95% B) approximately 68% C) at least 88.9% D) at least 75%

D)

According to insurance records, a car with a certain protection system will be recovered 93% of the time. If 800 stolen cars are randomly selected, what is the mean and standard deviation of the number of cars recovered after being stolen? A) mean: -5656: standard deviation: 7.21664742 B) mean: -5656: standard deviation: 52.08 C) mean: 744; standard deviation: 52.08 D) mean: 744; standard deviation: 7.21664742

D)

Assume that male and female births are equally likely and that the birth of any child does not affect the probability of the gender of any other children. Find the probability of at most three girls in ten births. A) 0.333 B) 0.003 C) 0.300 D) 0.172

D)

Consider the data in the table shown which represents the marital status of males and females 18 years or older in the United States in 2003. Determine the probability that a randomly selected U.S. resident 18 years or older is divorced or a male? Round to the nearest hundredth. A) 0.58 B) 0.04 C) 0.50 D) 0.54

D)

Consider the discrete probability distribution to the right when answering the following question. Find the probability that x equals 4. x 2 4 6 9 P(x) 0.12 ? 0.15 0.03 A) 1.2 B) 0.3 C) 2.8 D) 0.7

D)

Describe the shape of the histogram. The data set: round-trip commuting times (in minutes) of 20 randomly selected employees 135 120 115 132 136 124 119 145 98 110 125 120 115 130 140 105 116 121 125 108 A) symmetric B) skewed to the left C) uniform D) skewed to the right

D)

For the distribution drawn here, identify the mean, median, and mode. A) A = mode, B = mean, C = median B) A = mean, B = mode, C = median C) A = median, B = mode,C = mean D) A = mode, B = median, C = mean

D)

For the stem-and-leaf plot below, what are the maximum and minimum entries? 1 3 4 1 6 6 6 7 8 9 2 0 1 1 2 3 4 4 5 6 6 2 7 7 7 8 8 9 9 9 3 0 1 1 2 3 4 4 5 5 3 6 6 6 7 8 8 9 9 4 1 3 A) max: 41; min: 13 B) max: 38; min: 7 C) max: 47; min: 14 D) max: 43; min: 13

D)

Health care issues are receiving much attention in both academic and political arenas. A sociologist recently conducted a survey of citizens over 60 years of age whose net worth is too high to qualify for government health care but who have no private health insurance. The ages of 25 uninsured senior citizens were as follows: 68 73 66 76 86 74 61 89 65 90 69 92 76 62 81 63 68 81 70 73 60 87 75 64 82 Find Q2 of the data. A) 72 B) 74 C) 65.5 D) 73

D)

If A, B, C, and D, are the only possible outcomes of an experiment, find the probability of D using the table below. Outcome A B C D Probability 1/14 1/14 1/14 . A) 1/4 B) 3/14 C) 1/14 D) 11/14

D)

In a recent survey, 80% of the community favored building a health center in their neighborhood. If 15 citizens are chosen, what is the standard deviation of the number favoring the health center? A) 2.40 B) 0.55 C) 0.98 D) 1.55

D)

In the game of roulette in the United States a wheel has 38 slots: 18 slots are black, 18 slots are red, and 2 slots are green. The P(Red) = 18 38 ≈ 0.47. This is an example of what type of probability? A) Simulated B) Subjective C) Empirical D) Classical

D)

Make a scatter diagram for the data. Use the scatter diagram to describe how, if at all, the variables are related. x 6 11 9 8 12 7 y 2 5 3 3 4 1

D)

Many firms use on-the-job training to teach their employees new software. Suppose you work in the personnel department of a firm that just finished training a group of its employees in new software, and you have been requested to review the performance of one of the trainees on the final test that was given to all trainees. The mean and standard deviation of the test scores are 84 and 4, respectively, and the distribution of scores is bell shaped. What percentage of test-takers scored better than a trainee who scored 72? A) approximately 95% B) approximately 97.5% C) approximately 84% D) approximately 99.85%

D)

Parking at a large university has become a very big problem. University administrators are interested in determining the average parking time (e.g. the time it takes a student to find a parking spot) of its students. An administrator inconspicuously followed 300 students and carefully recorded their parking times. Identify the population of interest to the university administration. A) the students that park at the university between 9 and 10 AM on Wednesdays B) the parking times of the 300 students from whom the data were collected C) the entire set of faculty, staff, and students that park at the university D) the parking times of the entire set of students that park at the university

D)

Recently, the stock market took big swings up and down. A survey of 993 adult investors asked how often they tracked their portfolio. The table shows the investor responses. What is the probability that an adult investor tracks his or her portfolio daily? Express your answer as a simplified fraction and as a decimal rounded to three decimal places. A) 298/993 ; 0.3 B) 272/993 ; 0.274 C) 133/993 ; 0.134 D) 236/993 ; 0.238

D)

Sixty-five percent of men consider themselves knowledgeable soccer fans. If 12 men are randomly selected, find the probability that exactly four of them will consider themselves knowledgeable fans. A) 0.333 B) 0.65 C) 0.237 D) 0.020

D)

Solar energy is considered by many to be the energy of the future. A recent survey was taken to compare the cost of solar energy to the cost of gas or electric energy. Results of the survey revealed that the distribution of the amount of the monthly utility bill of a 3-bedroom house using gas or electric energy had a mean of $99 and a standard deviation of $9. If the distribution can be considered bell shaped, what percentage of homes will have a monthly utility bill of more than $90? A) approximately 32% B) approximately 16% C) approximately 95% D) approximately 84%

D)

The breakdown of workers in a particular state according to their political affiliation and type of job held is shown here. Suppose a worker is selected at random within the state and the worker's political affiliation and type of job are noted. Find the probability the worker is not an Independent. Round the the nearest hundredth. A) 0.47 B) 0.27 C) 0.26 D) 0.53

D)

The coefficient of determination is the _________of the linear correlation coefficient. A) opposite B) reciprocal C) square root D) square

D)

The commuting times (in minutes) of an employee for ten consecutive days are listed below. Find the median commute. 71 67 67 72 76 72 73 68 72 72 A) 71 minutes B) 67 minutes C) 73 minutes D) 72 minutes

D)

The conditional probability of event G, given the knowledge that event H has occurred, would be written as . A) P(H|G) B) P(G) C) P(H) D) P(G|H)

D)

The data below are the ages and annual pharmacy b ills (in dollars) of 9 randomly selected employees. Calculate the linear correlation coefficient. A) 0.998 B) 0.890 C) 0.908 D) 0.960

D)

The data below are the ages and systolic blood pressure (measured in Millimeters of mercury) of 9 randomly selected adults. A) 1.41 B) 1.99 C) 11.11 D) 123.63

D)

The data below are the average one-way commute times (in minutes) of selected students during a summer literature class and the number of absences for those students for the term. Calculate the linear correlation coefficient. A) 0.890 B) 0.819 C) 0.881 D) 0.980

D)

The data below are the final exam scores of 10 randomly selected history students and the number of hours they slept the night before the exam. Find the equation of the regression line for the given data. What would be the predicted score for a history student who slept 15 hours the previous night? Is this a reasonable question? Round your predicted score to the nearest whole number. Round the regression line values to the nearest hundredth. A) y ^ = -5.04x + 56.11; -20; No, it is not reasonable. B) y ^ = -5.04x + 56.11; -20; Yes, it is reasonable. C) y ^ = 5.04x + 56.11; 132; Yes, it is reasonable. D) y ^ = 5.04x + 56.11; 132; No, it is not reasonable. 15 hours is well outside the scope of the model

D)

The distribution of salaries of professional basketball players is skewed to the right. Which measure of central tendency would be the best measure to determine the location of the center of the distribution? A) mode B) mean C) frequency D) median

D)

The heights of ten male students (in inches) in a college biology class are listed below. Find the mean. 71 67 67 72 76 72 73 68 72 72 A) 67 inches B) 72 inches C) 68 inches D) 71 inches

D)

The manager of a used car lot took inventory of the automobiles on his lot and constructed the following table based on the age of his car and its make (foreign or domestic). A car was randomly selected from the lot. Given that the car selected is older than two years old, find the probability that it is not a foreign car A) 57/100 B) 57/112 C) 11/20 D) 55/112

D)

The managers of a corporation were surveyed to determine the background that leads to a successful manager. Each manager was rated as being either a good, fair, or poor manager by his/her boss. The manager's educational background was also noted. The data appear below. Given that a manager is only a fair manager, what is the probability that this manager has a college degree? A) 77/87 B) 21/80 C) 77/160 D) 14/29

D)

The one way distances from work (in miles) of 30 employees are listed below. Find Q2. 25 25 26 26.5 27 27 27.5 28 28 28.5 29 29 30 30 30.5 31 31 32 32.5 32.5 33 33 34 34.5 35 35 37 37 38 38 A) 31.75 mi B) 34 mi C) 28 mi D) 30.75 mi

D)

The owner of a farmer's market was interested in determining how many oranges a person buys when they buy oranges. He asked the cashiers over a weekend to count how many oranges a person bought when they bought oranges and record this number for analysis at a later time. The data is given below in the table. The random variable x represents the number of oranges purchased and P(x) represents the probability that a customer will buy x oranges. Determine the variance of the number of oranges purchased by a customer. A) 0.56 B) 1.95 C) 3.97 D) 3.57

D)

The percentage of measurements that are below the 88th percentile is A) 12% B) 22% C) cannot determine D) 88%

D)

The random variable x represents the number of tests that a patient entering a clinic will have along with the corresponding probabilities. Find the mean and standard deviation for the random variable x. A) mean: 1.59; standard deviation: 3.72 B) mean: 2.52; standard deviation: 1.93 C) mean: 3.72; standard deviation: 2.52 D) mean: 1.59; standard deviation: 1.09

D)

The regression line for the given data is y ^ = 0.449x - 30.27. Determine the residual of a data point for which x = 75 and y = 4. A) 7.405 B) 3.405 C) 103.474 D) 0.595

D)

The regression line for the given data is y ^ = 6.91x + 46.26. Determine the residual of a data point for which x = 7 and y = 93 A) 94.63 B) 187.63 C) -681.89 D) -1.63

D)

The sample space for tossing three fair coins is {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}. What is the probability of exactly two heads? A) 5/8 B) 3 C) 1/2 D) 3/8

D)

The table lists the drinking habits of a group of college students. If a student is chosen at random, find the probability of getting someone who is a regular or heavy drinker. Round your answer to three decimal places. Sex Non-drinker Regular Drinker Heavy Drinker Total Man 135 55 5 195 Woman 187 21 9 217 Total 322 76 14 412 A) 0.711 B) 0.155 C) 0.259 D) 0.218

D)

The table lists the drinking habits of a group of college students. If a student is chosen at random, find the probability of getting someone who is a woman or a heavy drinker. Round your answer to three decimal places A) 0.191 B) 0.921 C) 0.791 D) 0.526

D)

To avoid working late, the plant foreman inspects the first 20 microwaves produced that day. What sampling technique was used? A) stratified B) systematic C) cluster D) convenience E) simple random

D) convenience

The legal profession conducted a study to determine the percentage of cardiologists who had been sued for malpractice in the last three years. The sample was randomly chosen from a national directory of doctors. Identify the individuals in the study. A) the responses: have been sued/have not been sued for malpractice in the last three years B) the doctor's area of expertise (i.e., cardiology, pediatrics, etc.) C) all cardiologists in the directory D) each cardiologist selected from the directory

D) each cardiologist selected from the directory

What will help insure that the effect of a treatment is not due to some characteristic of a single experimental unit? A) randomizing B) blocking C) blinding D) replication

D) replication

The data set: Pick Three Lottery Outcomes for 10 Consecutive Weeks 3 6 7 6 0 6 1 7 8 4 1 5 7 5 9 1 5 3 9 9 2 2 3 0 8 8 4 0 2 4 A) bell shaped B) skewed to the left C) skewed to the right D) uniform

D) uniform

Computing Probability Using the Classical Metho

If an experiment has n equally likely outcomes and if the number of ways that an event E can occur is m, then the probability of E, P(E) is

Relation Between the Mean, Median, and Distribution Shape Distribution Shape Mean versus Median Skewed right

Mean substantially larger than media

Relation Between the Mean, Median, and Distribution Shape Distribution Shape Mean versus Median Skewed left

Mean substantially smaller than media

According to the American Veterinary Medical Association, 31.6% of American households own a dog. What is the probability that a randomly selected household does not own a dog?

P(do not own a dog) = 1 −P(own a dog)= 1 − 0.316= 0.684

Determine whether a Linear Relation Exists between Two Variables Testing for a Linear Relationship

Step 1 Determine the absolute value of the correlation coefficient. Step 2 Find the critical value in Table II for the given sample size. Step 3 If the absolute value of the correlation coefficient is greater than the critical value, we say a linear relation exists between the two variables. Otherwise, no linear relation exists

Drawing a boxplot

Step 1 Determine the lower and upper fences.Lower Fence = Q1− 1.5(IQR)Upper Fence = Q3 + 1.5(IQR)where IQR = Q3−Q1 Step 2 Draw a number line long enough to include the maximum and minimum values. Insert vertical lines at Q1, M, and Q3. Enclose these vertical lines in a box. Step 3 Label the lower and upper fence Step 4 Draw a line from Q1 to the smallest data value that is larger than the lower fence. Draw a line from Q3 to the largest data value that is smaller than the upper fence. These lines are called whiskers. Step 5 Any data values less than the lower fence or greater than the upper fence are outliers and are marked with an asterisk

EXAMPLE Computing Probabilities Using the Classical Method Suppose a "fun size" bag of M&Ms contains 9 brown candies, 6 yellow candies, 7 red candies, 4 orange candies, 2 blue candies, and 2 green candies. Suppose that a candy is randomly selected.(a) What is the probability that it is yellow? (b) What is the probability that it is blue? (c) Comment on the likelihood of the candy being yellow versus bl

a. 0.2 b.0.06 c. yellow, has a greater chance

interval level of measurement

has the properties of the ordinal level of measurement and the differences in the values of the variable have meaning. A value of zero in the interval level of measurement does not mean the absence of the quantity. Arithmetic operations such as addition and subtraction can be performed on values of the variable

The five-number summary of a set of data consists of the smallest data value, Q1, the median, Q3, and the largest data value. We organize the five-number summary as follow

min Q1 med Q3 max

blinding refers to

nondisclosure of the treatment an experimental unit is receiving.

Confounding in a study occurs when the effects of two or more explanatory variables are

not separated. Therefore, any relation that may exist between an explanatory variable and the response variable may be due to some other variable or variables not accounted for in the study.

There are two methods for collecting data, in research

observational studies and designed experiments

A convenience sample is one in which the individuals in the sample are easily

obtained

Skewed right

the tail to the right of the peak is longer than the tail to the left of the peak

The coefficient of determination, R2, measures the proportion of

total variation in the response variable that is explained by the least-squares regression line. The coefficient of determination is a number between 0 and 1, inclusive. That is, 0 <R2< 1. If R2 = 0 the line has no explanatory value If R2 = 1 means the line explains 100% of the variation in the response var

nominal level of measurement

variables whose values have no mathematical interpretation; they vary in kind or quality but not in amount

A single-blind experiment is one in which the experimental unit (or subject) does not know

which treatment he or she is receiving.

A random variable is A) a numerical measure of the outcome of a probability experiment. B) generated by a random number table. C) the variable for which an algebraic equation is solved. D) a qualitative attribute of a population.

A)

) A student is asked to rate a guest speaker's ability to communicate on a scale of poor-average-good-excellent. The student is to fill in a corresponding circle on a bubble form. This is an example of collecting what type of data? A) continuous B) insightful C) qualitative D) discrete

C)

) Each year advertisers spend billions of dollars purchasing commercial time on network sports television. In the first 6 months of 1988, advertisers spent $1.1 billion. A recent article listed the top 10 leading spenders (in millions of dollars): Company A $70 Company F $26.3 Company B 61.3 Company G 26.1 Company C 57.5 Company H 22.5 Company D 56.3 Company I 22.1 Company E 28.7 Company J 19.7 Calculate the mean amount spent. A) 384.88 million dollars B) 19.62 million dollars C) 39.05 million dollars D) 50.30 million dollars

C)

) A quiz consists of 60 multiple choice questions, each with five possible answers, only one of which is correct. If a student guesses on each question, what is the mean and standard deviation of the number of correct answers? A) mean: 12; standard deviation: 3.46410162 B) mean: 30; standard deviation: 5.47722558 C) mean: 30; standard deviation: 3.09838668 D) mean: 12; standard deviation: 3.09838668

D)

Checking for Outliers by Using Quartiles

Step 1 Determine the first and third quartiles of the data. Step 2 Compute the interquartile range. Step 3 Determine the fences. Fences serve as cutoff points for determining outliers.Lower Fence = Q1− 1.5(IQR)Upper Fence = Q3 + 1.5(IQR) Step 4 If a data value is less than the lower fence or greater than the upper fence, it is considered an outlie

interpretation of the Mean of a Discrete Random Variable

Suppose an experiment is repeated n independent times and the value of the random variable X is recorded. As the number of repetitions of the experiment increases, the mean value of the n trials will approach μX, the mean of the random variable X. In other words, let x1 be the value of the random variable X after the first experiment, x2 be the value of the random variable X after the second experiment, and so on. Then

Binomial Probability Distribution Function

The probability of obtaining x successes in n independent trials of a binomial experiment is given b

qualitative or categorical variables

allow for classification of individuals based on some attribute or characteristic

Probability is a measure of the likelihood of a

random phenomenon or chance behavior occurring. Probability describes the long-term proportion with which a certain outcome will occur in situations with short-term uncertaint

You roll two dice and total the up faces. What is the probability of getting a total of 8 or two up faces that are the same? Round the the nearest hundredth. A) 0.28 B) 0.50 C) 0.31 D) 0.33

A)

he percentage of measurements that are above the 39th percentile is A) 61% B) cannot determine C) 39% D) 71%

A)

the number of bottles of juice sold in a cafeteria during lunch A) discrete B) continuou

A)

Rules of probabilities

1. The probability of any event E, P(E), must be greater than or equal to 0 and less than or equal to 1 2. The sum of the probabilities of all outcomes must equal 1

x -7 -5 2 -1 -3 -4 -2 0 1 -6 y 20 15 3 8 12 13 10 5 4 17 A) r = -0.885; linear relation exists B) r = -0.995; no linear relation exists C) r = -0.995; linear relation exists D) r = -0.885; no linear relation exists

C)

Conditional Probability

The notation P(F|E) is read "the probability of event F given event E". It is the probability that the event F occurs given that event E has occurred.

If the value of a variable is measured at different points in time, the data are referred to as

time series data

Mark retired from competitive athletics last year. In his career as a sprinter he had competed in the 100-meters event a total of 328 times. His average time for these 328 races was 10.23 seconds. A) parameter B) statistic

A)

The average age of the 65 students in Ms. Hope's political science class is 21 years 6 months. A) parameter B) statistic

A)

Cross-sectional Studies

Observational studies that collect information about individuals at a specific point in time, or over a very short period of time. An advantage of cross-sectional studies is that they are cheap and quick to do. However, they have limitations. For our lung cancer study, individuals might develop cancer after the data are collected, so our study will not give the full picture.

Statics

is the science of collecting, organizing, summarizing, and analyzing information to draw conclusions or answer questions. In addition, statistics is about providing a measure of confidence in any conclusions.

Ratio Level of Measurement

it has the properties of the interval level of measurement and the ratios of the values of the variable have meaning. A value of zero in the ratio level of measurement means the absence of the quantity. Arithmetic operations such as multiplication and division can be performed on the values of the variable.

Problem Determine whether the following variables are qualitative or quantitative. (a) Gender (b) Temperature (c) Number of days during the past week that a college student studied (d) Zip code

a. qualitative quantitative quantitative qualitative

problem with cohort studies is that individuals tend to

drop out due to the long time frame. This could lead to misleading results. That said, cohort studies are the most powerful of the observational studies

observational study

measures the value of the response variable without attempting to influence the value of either the response or explanatory variables. That is, in an observational study, the researcher observes the behavior of the individuals without trying to influence the outcome of the study.

A continuous variable is a quantitative variable that has an

infinite number of possible values that are not countable. A continuous variable may take on every possible value between any two values

Descriptive statistics consist of

organizing and summarizing data. Descriptive statistics describe data through numerical summaries, tables, and graphs.

A parameter is a numerical summary of a

population Example: Suppose 48.2% of all students on your campus own a car. This value represents a parameter because it is a numerical summary of a population

Quantitative variables

provide numerical measures of individuals. The values of a quantitative variable can be added or subtracted and provide meaningful results.

A statistic is a numerical summary of a

sample Example: Suppose a sample of 100 students is obtained, and from this sample we find that 46% own a car. This value represents a statistic because it is a numerical summary of a sample

Which of the following is not true about factors? A) Factors whose effect on the response variable interests us should be set at predetermined levels. B) Any combination of the values of the factors is called a treatment. C) Factors whose effect on the response variable is not of interest can be set after the experiment. D) One way to control factors is to fix their level at one predetermined value throughout the experiment.

C

A control group serves as a baseline treatment that can be used to

compare to other treatments

A card is drawn from a standard deck of 52 playing cards. Find the probability that the card is a picture card. A) 4/13 B) 1/13 C) 3/13 D) 8/13

C)

The relative frequency is the proportion (or percent) of observations within a category and is found using the formula

RF= F/sum of all frequencies

The arithmetic mean of a variable is computed by

adding all the values of the variable in the data set and dividing by the number of observation

Which of the following probabilities for the sample points A, B, and C could be true if A, B, and C are the only sample points in an experiment? A) P(A) = -1/4, P(B) = 1/2, P(C) = 3/4 B) P(A) = 0, P (B) = 1/15, P(C) = 14/15 C) P(A) = 1/9, P(B) = 1/9, P(C) = 1/9 D) P(A) = 1/5, P(B) = 1/8, P(C) = 1/6

(B)

if an event is impossible, the probability of the event is

0. If an event is a certainty, the probability of the event is 1. An unusual event is an event that has a low probability of occurring

steps in designing an experiment

1. Identify the problem to be solved 2. Determine the factors that affect the response variable 3. Determine the number of experimental units 4. Determine the level of each factor 5. Conduct the experiment 6. Test the claim

Step 4: Determine the level of the predictor variables

1.Control: There are two ways to control the factors. a)Set the level of a factor at one value throughout the experiment (if you are notinterested in its effect on the response variable) .b)Set the level of a factor at various levels (if you are interested in its effect on the response variable). The combinations of the levels of all varied factors constitute the treatments in the experiment 2.Randomize: Randomize the experimental units to various treatment groups so that the effects of variables whose level cannot be controlled is minimized. The idea is that randomization "averages out" the effect of uncontrolled predictor variables

) The following data represents a random sample of 15 complaints registered with the customer service department of a store. Determine the median complaint. Other defective product excessive waiting time Messy store other other Messy store other messy store Other messy store messy store Defective product other messy store A) No median B) Excessive waiting time C) Messy store D) Defective product

A)

) The weights (in pounds) of babies born at St Mary's hospital last month are summarized in the table. Weight (lb) Number of Babies 5.0 - 5.8 8 5.9 - 6.7 18 6.8 - 7.6 20 7.7 - 8.5 9 8.6 - 9.4 4 Find the class width. A) 0.9 lb B) 0.8 lb C) 0.85 lb D) 0.95 lb

A)

The payroll amounts for 26 major-league baseball teams are shown below. Aprroximately what percentage of the payrolls were in the $30-$40 million range? Round to the nearest whole percent. A) 31% B) 8% C) 19% D) 42%

A)

The data set: ages of dishwashers (in years) in 20 randomly selected households 12 6 4 9 11 1 7 8 9 8 9 13 5 15 7 6 8 8 2 1 A) bell shaped B) skewed to the left C) skewed to the right D) uniform

A) bell shaped

the number of calls received at a company's help desk A) quantitative B) qualitative

A) quantitative

the temperatures of cups of coffee served at a restaurant A) quantitative B) qualitative

A) quantitative

) A researcher records the number of employees of each of the IT companies in the town of Westmoore. The results are summarized in the table. Number of Employees Number of IT Companies 0 - 399 32 400 - 799 21 800 - 1199 5 1200 - 1599 10 1600 - 1999 10 Find the class limits of the third class. A) lower limit: 799; upper limit: 1200 B) lower limit: 800; upper limit: 1199 C) lower limit: 800; upper limit: 1200 D) lower limit: 799.5; upper limit: 1199.5

B)

) In distributions that are skewed to the right, what is the relationship of the mean, median, and mode? A) mode > median > mean B) mean > median > mode C) mode > mean > median D) median > mean > mode

B)

) The data below are the final exam scores of 10 randomly selected chemistry students and the number of hours they slept the night before the exam. What is the best predicted value for y given x = 5? A) 80 B) 81 C) 79 D) 82

B)

51.3% of the residents of Idlington Garden City are female. A) statistic B) parameter

B)

A farmer wishes to test the effects of a new fertilizer on her potato yield. She has four equal-sized plots of land-- one with sandy soil, one with rocky soil, one with clay-rich soil, and one with average soil. She divides each of the four plots into three equal-sized portions and randomly labels them A, B, and C. The four A portions of land are treated with her old fertilizer. The four B portions are treated with the new fertilizer, and the four C's are treated with no fertilizer. At harvest time, the potato yield is recorded for each section of land. What type of experimental design is this? A) completely randomized design B) randomized block design C) matched-pairs design D) double-blind design

B)

A farmer wishes to test the effects of a new fertilizer on her wheat yield. She has four equal-sized plots of land-- one with sandy soil, one with rocky soil, one with clay-rich soil, and one with average soil. She divides each of the four plots into three equal-sized portions and randomly labels them A, B, and C. The four A portions of land are treated with her old fertilizer. The four B portions are treated with the new fertilizer, and the four C's are treated with no fertilizer. At harvest time, the wheat yield is recorded for each section of land. Identify the experimental units. A) the three types of fertilizer B) the wheat plants on the various plots of land C) the four types of soil D) the wheat yield at harvest time

B)

In the game of craps two dice are rolled and the up faces are totaled. If the person rolling the dice on the first roll rolls a 7 or an 11 total they win. If they roll a 2, 3, or 12 on the first roll they lose. If they roll any other total then on subsequent rolls they must roll that total before rolling a 7 to win. What is the probability of winning on the first roll? A) 0.50 B) 0.22 C) 0.17 D) 0.06

B)

SAS was used to compare the high school dropout rates for the 30 school districts in one city in 2010 and 2012. The box plots generated for these dropout rates are shown below. Compare the center of the distributions and the variation of the distributions for the two years. YEAR 2010 2012 A) Dropout rates had a lower average with more variability in 2010 than in 2012. B) Dropout rates had a higher average with less variability in 2010 than in 2012. C) Dropout rates had a higher average with more variability in 2010 than in 2012. D) Dropout rates had a lower average with less variability in 2010 than in 2012.

B)

When results from a scholastic assessment test are sent to test-takers, the percentiles associated with their scores are also given. Suppose a test-taker scored at the 96th percentile for their verbal grade and at the 37th percentile for their quantitative grade. Interpret these results. A) This student performed better than 96% of the other test-takers in the verbal part and better than 63% in the quantitative part. B) This student performed better than 96% of the other test-takers in the verbal part and better than 37% in the quantitative part. C) This student performed better than 4% of the other test-takers in the verbal part and better than 63% in the quantitative part. D) This student performed better than 4% of the other test-takers in the verbal part and better than 37% in the quantitative part.

B)

he cost of a road atlas A) continuous B) discrete

B)

the age of the oldest dog in a kennel A) discrete B) continuous

B)

the heights of the bookcases in a school library A) discrete B) continuous

B)

the pressure of water coming out of a fire hose A) discrete B) continuous

B)

Who got the most votes? A) Gina B) Ted C) Ann D) Matt

B) Ted

The object upon which the response variable is measured is called ________ . A) the factor B) an experimental unit C) a treatment D) the predictor variable

B) an experimental unit

he data set: weekly grocery bills (in dollars) for 20 randomly selected households 135 120 115 132 136 124 119 145 98 110 125 120 115 130 140 105 116 121 125 108 A) skewed to the right B) bell shaped C) uniform D) skewed to the left

B) bell shaped

Researchers wanted to determine whether there was an association between city driving and stomach ulcers. They selected a sample of 900 young adults and followed them for a twenty-year period. At the start of the study none of the participants was suffering from a stomach ulcer. Each person kept track of the number of hours per week they spent driving in city traffic. At the end of the study each participant underwent tests to determine whether they were suffering from a stomach ulcer. The researchers analyzed the results to determine whether there was an association between city driving and stomach ulcers. A) retrospective; Individuals are asked to look back in time. B) cohort; Individuals are observed over a long period of time. C) cross-sectional; Information is collected at a specific point in time.

B) cohort; Individuals are observed over a long period of time.

the native language of a tourist A) ordinal B) nominal C) interval D) ratio

B) nominal

the number of seats in a school auditorium A) qualitative B) quantitative

B) quantitative

Find the population mean or sample mean as indicated. Sample: 5, 8, 13, 17, 22 A) μ = 12 B) μ = 13 C)-x = 13 D) -x = 14

C)

The events A and B are mutually exclusive. If P(A) = 0.7 and P(B) = 0.1, what is P(A or B)? A) 0.6 B) 0 C) 0.8 D) 0.07

C)

The top 38 cities in Wisconsin as determined by population are given below. Select a random sample of four cities from the list below using the two digit list of random numbers provided. Begin with the uppermost left random number and proceed down each column. When a column is complete, use the numbers at the top of the next right column and proceed down that column. Information was obtained from the web site http://www.citypopulation.de/USA-Wisconsin.html. Wisconsin Cities by Population A) Milwaukee, Eau Claire, New Berlin, West Bend. B) Milwaukee, Madison, Green Bay, Kenosha. C) Manitowoc, La Crosse, Franklin, Oshkosh. D) Manitowoc, Appleton, Greenfield, Fond du Lac

C)

The variable is the variable whose value can be explained by the variable. A) lurking; response B) predictor Response C) response; predictor D) response; lurking

C)

Which measure of central tendency may have more than one value in a numeric data set? A) Mean B) Midrange C) Mode D) Median

C)

Which of the following cannot be the probability of an event? A) 5/3 B) 0 C) -61 D) 0.001

C)

Use the graph to approximate the test score that corresponds to the 50th percentile? A) 20 B) 25 C) 62 D) 68

D)

Use the linear correlation coefficient given to determine the coefficient of determination, R2. r = 0.89 A) R2 = 94.34% B) R2 = 9.43% C) R2 = 7.921% D) R2 = 79.21%

D)

When the effects of the explanatory variable upon the response variable cannot be determined, then A) a lurking variable is present. B) there is sampling error. C) the claim is invalid. D) confounding has occurred.

D)

Which of the below is not a requirement for binomial experiment? A) For each trial there are two mutually exclusive outcomes. B) The experiment is performed a fixed number of times. C) The probability of success is fixed for each trial of the experiment. D) The trials are mutually exclusive

D)

the graph of a distribution of data shows that the graph is symmetric then the A) Median is a better measure of central tendency B) Mode is a better measure of central tendency C) Midrange is a better measure of central tendency D) Mean is a better measure of central tendency

D)

An education researcher randomly selects 30 of the nation's junior colleges and interviews all of the professors at each school. What sampling technique was used? A) systematic B) stratified C) simple random D) cluster E) convenience

D) cluster

Finding Quartiles

Step 1: Arrange the data in ascending order. Step 2: Determine the median, M, or second quartile, Q2 .Step 3: Divide the data set into halves: the observations below (to the left of) M and the observations above M. The first quartile, Q1, is the median of the bottom half, and the third quartile, Q3, is the median of the top half

The classical method of computing probabilities requires

equally likely outcomes. An experiment is said to have equally likely outcomes when each simple event has the same probability of occurring

Classes are categories into which data are

grouped. When a data set consists of a large number of different discrete data values or when a data set consists of continuous data, we must create classes by using intervals of number

A stratified sample is obtained by separating the population into

nonoverlapping groups called strata and then obtaining a simple random sample from each stratum. The individuals within each stratum should be homogeneous (or similar) in some

A completely randomized design is one in which each experimental unit is

randomly assigned to a treatment

A cluster sample is obtained by selecting all individuals within a

randomly selected collection or group of individuals

Bell-shaped distribution

the highest frequency occurs in the middle and frequencies tail off to the left and right of the middle

) Civil engineers often use the straight-line equation, y ^= β0 + β1x, to model the relationship between the mean shear strength of masonry joints and precompression stress, x. To test this theory, a series of stress tests were performed on solid bricks arranged in triplets and joined with mortar. The precompression stress was varied for each triplet and the ultimate shear load just before failure (called the shear strength) was recorded. The stress results for n = 7 triplet tests is shown in the accompanying table followed by a SAS printout of the regression analysis. Triplet Test 1 2 3 4 5 6 7 Shear Strength (tons), y 1.00 2.18 2.24 2.41 2.59 2.82 3.06 Precomp. Stress (tons), x 0 0.60 1.20 1.33 1.43 1.75 1.75 Give a practical interpretation of the estimate of the slope of the least squares line. A) For every 1 ton increase in precompression stress, we estimate the shear strength of the joint to increase by 0.987 ton. B) For a triplet test with a precompression stress of 0 tons, we estimate the shear strength of the joint to be 1.19 tons. C) For a triplet test with a precompression stress of 1 ton, we estimate the shear strength of the joint to be 0.987 ton. 35 D) For every 0.987 ton increase in precompression stress, we estimate the shear strength of the joint to increase by 1 ton.

A)

)Computing the probability of the event "drawing a second red ball from a bag of colored balls after having kept the red ball that was drawn first from the bag" is an example of A) conditional probability. B) mutual exclusiveness. C) independence of events. D) disjoint events.

A)

25.2% of the mayors of cities in a certain state are from minority groups. A) parameter B) statistic

A)

A certain disease only affects men 20 years of age or older. The chart shows the probability that a man with the disease falls in the given age group. What is the probability that a randomly selected man with the disease is not between the ages of 55 and 64? Age Group Probability 20-24 0.004 25-34 0.006 35-44 0.14 45-54 0.29 55-64 0.32 65-74 0.17 75+ 0.07 A) 0.68 B) 0.24 C) 0.32 D) 0.29

A)

A farmer wishes to test the effects of a new fertilizer on her soybean yield. She has four equal-sized plots of land-- one with sandy soil, one with rocky soil, one with clay-rich soil, and one with average soil. She divides each of the four plots into three equal-sized portions and randomly labels them A, B, and C. The four A portions of land are treated with her old fertilizer. The four B portions are treated with the new fertilizer, and the four C's are treated with no fertilizer. At harvest time, the soybean yield is recorded for each section of land. What is the treatment in this experiment? A) the fertilizers B) the soybean yield recorded for each section of land C) the four types of soil D) the section of land (A, B, or C)

A)

A history professor decides to give a 12-question true-false quiz. She wants to choose the passing grade such that the probability of passing a student who guesses on every question is less than 0.10. What score should be set as the lowest passing grade? A) 9 B) 10 C) 7 D) 8

A)

A medical journal published the results of an experiment on anorexia. The experiment investigated the effects of a controversial new therapy for anorexia. Researchers measured the anorexia levels of 79 adult women who suffer moderate conditions of the disorder. After the therapy, the researchers again measured the women's anorexia levels. The differences between the the pre- and post-therapy anorexia levels were reported. Identify the experimental units. A) the 79 adult women who suffer from anorexia B) the therapy time period (pre or post) C) the disorder (anorexia or no anorexia) D) the differences between the pre- and post-therapy anorexia levels

A)

A medical journal published the results of an experiment on depression. The experiment investigated the effects of a controversial new therapy for depression. Researchers measured the depression levels of 79 adult women who suffer moderate conditions of the disorder. After the therapy, the researchers again measured the women's depression levels. The differences between the the pre- and post-therapy depression levels were reported. How many levels does the treatment have in this experiment? A) 2 (pre- and post-therapy) B) 1 (therapy) C) 158 (the adult women who suffer from depression measured pre- and post-therapy) D) 79 (the adult women who suffer from depression)

A)

A pharmaceutical testing company wants to test a new cholesterol drug. The average cholesterol of the target population is 200 mg and they have a standard deviation of 25 mg. The company wished to test a sample of people who fall between 1.5 and 3 z-scores above the mean. Into what range must a candidate's cholesterol level be in order for the candidate to be included in the study? A) 237.5 - 275 B) 162.5 - 275 C) 225 - 237.5 D) 125 - 162.5

A)

A random number generator is set to generate single digits between 0 and 9. One hundred and fifty random numbers are generated. The probability distribution for this random number generator is given below. What is the mean of this distribution? x 0 1 2 3 4 5 6 7 8 9 P(x) 0.09 0.12 0.11 0.08 0.09 0.13 0.10 0.07 0.10 0.11 A) 4.5 B) 7 C) 5 D) 6.6

A)

A researcher at a large university wanted to investigate if a student's seat preference was related in any way to the gender of the student. The researcher divided the lecture room into three sections (1-front, middle of the room, 2-front, sides of the classroom, and 3-back of the classroom, both middle and sides) and noted where his students sat on a particular day of the class. The researcher's summary table is provided below. Suppose a person sitting in the front, middle portion of the class is randomly selected to answer a question. Find the probability the person selected is a female. A) 13/33 B) 13/72 C) 11/13 D) 1/3

A)

A(n) _______________ of a probability experiment is the collection of all outcomes possible. A) Sample space B) Prediction set C) Event set D) Bernoulli space

A)

Classify the statement as an example of classical probability, empirical probability, or subjective probability. The probability that a newborn kitten is a male is 1/2 . A) classical probability B) subjective probability C) empirical probability

A)

Compute the linear correlation coefficient between the two variables and determine whether a linear relation exists. x 2 3 5 5 6 y 1.3 1.6 2.1 2.2 2.7 A) r = 0.983; linear relation exists B) r = 0.883; linear relation exists C) r = 0.883; no linear relation exists D) r = 0.983; no linear relation exists

A)

Describe the shape of the histogram. The data set: Pick-Three lottery results for 10 consecutive weeks 3 6 7 6 0 6 1 7 8 4 1 5 7 5 9 1 5 3 9 9 2 2 3 0 8 8 4 0 2 4 A) uniform B) symmetric C) skewed to the right D) skewed to the lef

A)

Explain what is misleading about the graphic. A) The graphic may give the impression that drivers over age 65 had no DUIʹs in 2012. B) The graphic only includes information for one year. C) The horizontal scale does not begin at zero. D) The graphic is not misleading.

A)

Explain what is misleading about the graphic. A) The vertical scale does not begin at zero. B) The trend is depicted in the wrong direction. C) The horizontal label is incomplete. D) The graphic is not misleading.

A)

Given the following least squares prediction equation, y^= -173 +74x, we estimate y to by with each 1-unit increase in x. A) increase; 74 B) decrease; 173 C) decrease; 74 D) increase; 173

A)

One hundred people were asked, "Do you favor stronger laws on gun control?" Of the 33 that answered "yes" to the question, 14 were male. Of the 67 that answered "no" to the question, six were male. If one person is selected at random, what is the probability that this person answered "yes" or was a male? Round the the nearest hundredth. A) 0.39 B) 0.67 C) 0.53 D) 0.13

A)

Suppose that E and F are two events and that P(E) = 0.2 and P(F E) = 0.3. What is P(E and F)? A) 0.06 B) 0.006 C) 0.5 D) 0.667

A)

Telephone interviews of 318 employees of a large electronics company found that 45% were dissatisfied with their working conditions. A) statistic B) parameter

A)

The overnight shipping business has skyrocketed in the last ten years. The single greatest predictor of a company's success has been proven time and again to be customer service. A study was conducted to study the customer satisfaction levels for one overnight shipping business. In addition to the customer's satisfaction level, the customers were asked how often they used overnight shipping. The results are shown below in the following table. A customer is chosen at random. Given that the customer uses the company two to five times per month, what is the probability that they expressed high satisfaction with the company? A) 7/10 B) 1/5 C) 7/23 D) 26/35

A)

the temperature in degrees Celsius on January 1st in Fargo, North Dakota A) continuous B) discrete

A)

) The table shows the number of days off last year and the earnings for the year (in thousands of dollars) for nine randomly selected insurance salesmen. A) r = -0.899; no linear relation exists B) r = -0.991; linear relation exists C) r = -0.991; no linear relation exists D) r = -0.899; linear relation exists

B)

A baseball player is asked to swing at pitches in sets of four. The player swings at 100 sets of 4 pitches. The probability distribution for making a particular number of hits is given below. Determine the mean for this discrete probability distribution. A) 4 B) 3 C) 2 D) 3.5

B)

A recent survey found that 70% of all adults over 50 wear sunglasses for driving. In a random sample of 10 adults over 50, what is the probability that at least six wear sunglasses? A) 0.006 B) 0.850 C) 0.200 D) 0.700

B)

In 5-card poker, played with a standard 52-card deck, 2,598,960 different hands are possible. If there are 624 different ways a "four-of-a-kind" can be dealt, find the probability of not being dealt a "four-of-a-kind". Express the probability as a fraction, but do not simplify. A) 624/2,598,960 B) 2,598,336/2,598,960 C) 625/2,598,960 D) 1248/2,598,960

B)

The annual profits of five large corporations in a certain area are given below. Which measure of central tendency should be used? $209,000 $217,000 $237,000 $207,000 $1,287,000 A) midrange B) median C) mean D) mode

B)

True or False: Conditional probabilities leave the sample space the same when considering sequential events. A) True B) False

B)

Use the graph to approximate the percentile rank of an individual whose test score is 50. A) 68 B) 20 C) 25 D) 63

B)

Which of the following is not true of statistics? A) Statistics involves collecting and summarizing data. B) Statistics is used to answer questions with 100% certainty. C) Statistics can be used to organize and analyze information. D) Statistics is used to draw conclusions using data

B.

A contingency table relates A) only continuous random variables. B) the difference in the means of two random variables. C) two categories of data. D) a particular response with order in which that response should be applied.

C)

A game has three outcomes. The probability of a win is 0.4, the probability of tie is 0.5, and the probability of a loss is 0.1. What is the probability of not winning in a single play of the game. A) 0.33 B) 0.1 C) 0.6 D) 0.5

C)

A single die is rolled twice. The set of 36 equally likely outcomes is {(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6), (2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6), (3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6), (4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (4, 6), (5, 1), (5, 2), (5, 3), (5, 4), (5, 5), (5, 6), (6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)}. Find the probability of getting two numbers whose sum is greater than 10. A) 3 B) 5/18 C) 1/12 D) 1/18

C)

Describe the shape of the histogram. The data set: age of 20 household stereo systems randomly selected from a neighborhood 12 6 4 9 11 1 7 8 9 8 9 13 5 15 7 6 8 8 2 1 A) skewed to the right B) skewed to the left C) symmetric D) uniform

C)

Find the equation of the regression line for the given data. Round values to the nearest thousandth. A) y= 1.885x - 0.758 B) y= 0.758x + 1.885 C) y= -1.885x + 0.758 D) y= -0.758x - 1.885

C)

The sum of the probabilities of a discrete probability distribution must be A) greater than one. B) less than or equal to zero. C) equal to one. D) between zero and one

C)

Use the linear correlation coefficient given to determine the coefficient of determination, R2. r = -0.28 A) R2 = 52.92% B) R2 = -7.84% C) R2 = 7.84% D) R2 = -52.92%

C)

You are dealt one card from a standard 52-card deck. Find the probability of being dealt an ace or a 6. A) 7 B) 13/2 C) 2/13 D) 7/26

C)

he data below are the average one-way commute times (in minutes) for selected students and the number of absences for those students during the term. Find the equation of the regression line for the given data. What would be the predicted number of absences if the commute time was 40 minutes? Is this a reasonable question? Round the predicted number of absences to the nearest whole number. Round the regression line values to the nearest hundredth. A) y= 0.45x - 30.27; -12 absences; Yes, it is reasonable. B) y= 0.45x + 30.27; 48 absences; Yes, it is reasonable. C) y= 0.45x - 30.27; -12 absences; No, it is not reasonable. 40 minutes is well outside the scope of the model. D) y= 0.45x + 30.27; 48 absences; No, it is not reasonable. 40 minutes is well outside the scope of the model.

C)

x 10 11 16 9 7 15 16 10 y 96 51 62 58 89 81 46 51 A) r = -0.284; no linear relation exists B) r = 0.462; linear relation exists C) r = -0.335; no linear relation exists D) r = -0.335; linear relation exists

C)

x 9 2 3 4 2 5 9 10 y 85 52 55 68 67 86 83 73 A) r = 0.708; no linear relation exists B) r = -0.708; linear relation exists C) r = 0.708; linear relation exists D) r = 0.235; no linear relation exists

C)

A statistics student interviews everyone in his apartment building to determine who owns a cell phone. What sampling technique is used? A) cluster B) simple random C) convenience D) stratified E) systematic

C) convenience

Researchers wanted to determine whether there was an association between high blood pressure and the suppression of emotions. The researchers looked at 1800 adults enrolled in a Health Initiative Observational Study. Each person was interviewed and asked about their response to emotions. In particular they were asked whether their tendency was to express or to hold in anger and other emotions. The degree of suppression of emotions was rated on a scale of 1 to 10. Each person's blood pressure was also measured. The researchers analyzed the results to determine whether there was an association between high blood pressure and the suppression of emotions. A) cohort; Individuals are observed over a long period of time. B) retrospective; Individuals are asked to look back in time. C) cross-sectional; Information is collected at a specific point in time.

C) cross-sectional; Information is collected at a specific point in time.

) The scores from a state standardized test have a mean of 80 and a standard deviation of 10. The distribution of the scores is roughly bell shaped. Use the Empirical Rule to find the percentage of scores that lie between 60 and 80. A) 68% B) 95% C) 34% D) 47.5%

D)

A certain disease only affects men 20 years of age or older. The chart shows the probability that a man with the disease falls in the given age group. What is the probability that a randomly selected man with the disease is between the ages of 35 and 64? Age Group Probability 20-24 0.004 25-34 0.006 35-44 0.14 45-54 0.29 55-64 0.32 65-74 0.17 75+ 0.07 A) 0.14 B) 0.29 C) 0.32 D) 0.75

D)

A drug company wanted to test a new acne medication. The researchers found 600 adults aged 25-35 and randomly assigned them to two groups. The first group received the new drug, while the second received a placebo. After one month of treatment, the percentage of each group whose acne symptoms decreased was recorded and compared. How many levels does the treatment in this experiment have? A) 600 (number of respondents) B) 1 (months of treatment) C) 10 (age span of respondents) ' D) 2 (medication or placebo)

D)

A quiz consists of 10 true or false questions. To pass the quiz a student must answer at least eight questions correctly. If the student guesses on each question, what is the probability that the student will pass the quiz? A) 0.20 B) 0.08 C) 0.8 D) 0.055

D)

According to the Federal Communications Commission, 70% of all U.S. households have vcrs. In a random sample of 15 households, what is the probability that exactly 10 have vcrs? A) 0.7939 B) 0.7 C) 0.5 D) 0.2061

D)

An Excel printout of some descriptive statistics for a set of data is shown below. What is the IQR? A) 15 B) 38 C) 5.5 D) 15.5

D)

Given the equation of a regression line is y= -4.5x- 2.4, what is the best predicted value for y given x = 2.3? A) 7.95 B) -7.95 C) 12.75 D) -12.75

D)

Health care issues are receiving much attention in both academic and political arenas. A sociologist recently conducted a survey of senior citizens whose net worth is too high to qualify for government health care but who have no private health insurance. The ages of 25 uninsured senior citizens were as follows: 72 77 70 80 90 78 65 93 69 94 73 96 80 66 85 67 72 85 74 77 64 91 79 68 86 Find Q1 of the data. A) 70 B) 69 C) 77.5 D) 69.5

D)

If the coefficient of determination is close to 1, then A) the linear correlation coefficient is close to zero. B) the least squares regression line equation has no explanatory value. C) the sum of the square residuals is large compared to the total variation. D) the least squares regression line equation explains most of the variation in the response variable

D)

In which scatter diagram is r = -1? A) d B) b C) f D) a

D)

The ______________ probability of an outcome is obtained by dividing the frequency of occurrence of an event by the number of trials of the experiment. A) Classical B) Subjective C) Conditional D) Empirical

D)

A lobbyist for the oil industry assigns a number to each senator and then uses a computer to randomly generate ten numbers. The lobbyist contacts the senators corresponding to these numbers. What sampling technique was used? A) systematic B) cluster C) stratified D) convenience E) simple random

E) simple random

Thirty-five math majors, 56 music majors and 26 history majors are randomly selected from 403 math majors, 315 music majors and 512 history majors at the state university. What sampling technique is used? A) cluster B) convenience C) systematic D) simple random E) stratified

E) stratified

The Addition Rule for Disjoint Events can be extended to more than two disjoint events. In general, if E, F, G, . . . each have no outcomes in common (they are pairwise disjoint), the

E+ F+G+H+I+J......=1

Relation Between the Mean, Median, and Distribution Shape Distribution Shape Mean versus Median Symmetric

Mean roughly equal to median

Organize Discrete Data in Tables

The first step in summarizing quantitative data is to determine whether the data are discrete or continuous. If the data are discrete and there are relatively few different values of the variable, the categories of data (classes) will be the observations (as in qualitative data). If the data are discrete, but there are many different values of the variables, or if the data are continuous, the categories of data (the classes) must be created using intervals of numbers

ordinal level of measurement

classifies data into categories that can be ranked; however, precise differences between the ranks do not exist -has the properties of the nominal level of measurement and the naming scheme allows for the values of the variable to be arranged in a ranked, or specific, ord

A discrete variable is a quantitative variable that has either a

finite number of possible values or a countable number of possible values. The term countable means that the values result from counting, such as 0, 1, 2, 3, and so on. A discrete variable cannot take on every possible value between any two possible values.

A placebo is an

innocuous medication, such as a sugar tablet, that looks, tastes, and smells like the experimental medication

The range, R, of a variable is the difference between the

largest data value and the smallest data values. That is,Range = R = Largest Data Value − Smallest Data Value

A stem-and-leaf plot uses digits to the

left of the rightmost digit to form the stem. Each rightmost digit forms a leaf. For example, a data value of 147 would have 14 as the stem and 7 as the leaf

A frequency distribution

lists each category of data and the number of occurrences for each category of data

Probability deals with experiments that yield random short-term results or outcomes, yet reveal

long-term predictability. The long-term proportion in which a certain outcome is observed is the probability of that outcome

Case-control Studies, these studies are retrospective, meaning that they require individuals to

look back in time or require the researcher to look at existing records. In case-control studies, individuals who have certain characteristics are matched with those that do not

A sample of size n from a population of size N is obtained through simple random sampling if every possible sample of size n has an equally likely chance of occurring. The sample is then called a

simple random sample

The lower class limit of a class is the

smallest value within the class

The sample standard deviation, s, of a variable is the

square root of the sum of squared deviations about the sample mean divided by n− 1, where n is the sample size

the medal received (gold, silver, bronze) by an Olympic gymnast A) interval B) ratio C) nominal D) ordinal

D) ordinal

There are three major categories of observational studies:

(1) cross-sectional studies, (2) case-control studies (3) cohort studies.

The government of a town needs to determine if the city's residents will support the construction of a new town hall. The government decides to conduct a survey of a sample of the city's residents. Which one of the following procedures would be most appropriate for obtaining a sample of the town's residents? A) Survey a random sample of persons within each geographic region of the city. B) Survey every 7th person who walks into city hall on a given day. C) Survey the first 500 people listed in the town's telephone directory. D) Survey a random sample of employees at the old city hall.

A)

the age of the oldest employee in the data processing department A) continuous B) discrete

A) continuous

the cholesterol levels of a group of adults the day after Thanksgiving A) continuous B) discrete

A) continuous

A poll is conducted in which professional musicians are asked their ages. A) observational study B) experiment

A) observational study

A researcher obtained a random sample of 100 smokers and a random sample of 100 nonsmokers. After interviewing all 200 participants in the study, the researcher compared the rate of depression among the smokers with the rate of depression among nonsmokers. A) observational study B) experiment

A) observational study

The personnel director at a large company would like to determine whether the company cafeteria is widely used by employees. She calls each employee and asks them whether they usually bring their own lunch, eat at the company cafeteria, or go out for lunch. A) observational study B) experiment

A) observational study

the native languages of students in an English class A) qualitative B) quantitative

A) qualitative

the numbers on the shirts of a boy's football team A) qualitative B) quantitative

A) qualitative

) The city council of a small town needs to determine if the town's residents will support the building of a new library. The council decides to conduct a survey of a sample of the town's residents. Which one of the following procedures would be most appropriate for obtaining a sample of the town's residents? A) Survey 300 individuals who are randomly selected from a list of all people living in the state in which the town is located. B) Survey a random sample of persons within each neighborhood of the town. C) Survey every 13th person who enters the old library on a given day. D) Survey a random sample of librarians who live in the town

B)

A study of 3100 college students in the city of Pemblington found that 4% had been victims of violent crimes. A) parameter B) statistic

B)

In a survey conducted in the town of Atherton, 29% of adult respondents reported that they had been involved in at least one car accident in the past ten years. A) parameter B) statistic

B)

The peak shopping time at a pet store is between 8-11:00 am on Saturday mornings. Management at the pet store randomly selected 95 customers last Saturday morning and decided to observe their shopping habits. They recorded the number of items that a sample of the customers purchased as well as the total time the customers spent in the store. Identify the types of variables recorded by the pet store. A) number of items - continuous; total time - continuous B) number of items - discrete; total time - continuous C) number of items - discrete; total time - discrete D) number of items - continuous; total time - discrete

B)

Which branch of statistics deals with the organization and summarization of collected information? A) Inferential statistics B) Descriptive statistics C) Computational statistics D) Survey design

B) Descriptive statistics

The number of violent crimes committed in a city on a given day in a random sample of 100 days is a __________ random variable. A) continuous B) discrete

B) discrete

the number of bottles of juice sold in a cafeteria during lunch A) continuous B) discrete

B) discrete

the number of goals scored in a hockey game A) continuous B) discrete

B) discrete

A medical researcher obtains a sample of adults suffering from diabetes. She randomly assigns 73 people to a treatment group and 73 to a placebo group. The treatment group receives a medication over a period of three months and the placebo group receives a placebo over the same time frame. At the end of three months the patients' symptoms are evaluated. A) observational study B) experiment

B) experiment

A scientist was studying the effects of a new fertilizer on crop yield. She randomly assigned half of the plots on a farm to group one and the remaining plots to group two. On the plots in group one, the new fertilizer was used for a year. On the plots in group two, the old fertilizer was used. At the end of the year the average crop yield for the plots in group one was compared with the average crop yield for the plots in group two. A) observational study B) experiment

B) experiment

the musical instrument played by a music student A) ratio B) nominal C) interval D) ordinal

B) nominal

an officer's rank in the military A) interval B) ordinal C) ratio D) nominal

B) ordinal

Parking at a large university has become a very big problem. University administrators are interested in determining the average parking time (e.g. the time it takes a student to find a parking spot) of its students. An administrator inconspicuously followed 210 students and carefully recorded their parking times. Identify the sample of interest to the university administration. A) parking time of a student B) parking times of the 210 students C) location of the parking spot D) type of car (import or domestic)

B) parking times of the 210 students

Vitamin D is important for the metabolism of calcium and exposure to sunshine is an important source of vitamin D. A researcher wanted to determine whether osteoperosis was associated with a lack of exposure to sunshine. He selected a sample of 250 women with osteoperosis and an equal number of women without osteoperosis. The two groups were matched - in other words they were similar in terms of age, diet, occupation, and exercise levels. Histories on exposure to sunshine over the previous twenty years were obtained for all women. The total number of hours that each woman had been exposed to sunshine in the previous twenty years was estimated. The amount of exposure to sunshine was compared for the two groups. A) cross-sectional; Information is collected at a specific point in time. B) retrospective; Individuals are asked to look back in time C) cohort; Individuals are observed over a long period of time.

B) retrospective; Individuals are asked to look back in time

A bicycle manufacturer produces four different bicycle models. Information is summarized in the table below: Model Series Number Weight Style Ascension A120 32 Mountain Road Runner B640 21 Road All Terrain C300 27 Hybrid Class Above D90 15 Racing Identify the variables and determine whether each variable is quantitative or qualitative. A) series number: quantitative; weight: quantitative; style: qualitative B) series number: qualitative; weight: qualitative; style: qualitative C) series number: qualitative; weight: quantitative; style: qualitative D) series number: quantitative; weight: qualitative; style: qualitative

C)

A manufacturer of cellular phones has decided that an assembly line is operating satisfactorily if less than 0.03% of the phones produced per day are defective. To check the quality of a day's production, the company decides to randomly sample 10 phones from a day's production to test for defects. Define the population of interest to the manufacturer. A) the 10 phones sampled and tested B) the 0.03% of the phones that are defective C) all the phones produced during the day in question D) the 10 responses: defective or not defective

C)

An international relations professor is supervising four master's students. Information about the students is summarized in the table. Student Name Student Number Area of Interest GPA Anna 914589205 Africa 3.73 Pierre 981672635 Middle East 3.31 Juan 906539012 Latin America 3.34 Yoko 977530271 Asia 3.80 Identify the variables and determine whether each variable is quantitative or qualitative. A) student number: quantitative; area of interest: qualitative; GPA: qualitative B) student number: quantitative; area of interest: qualitative; GPA: quantitative C) student number: qualitative; area of interest: qualitative; GPA: quantitative D) student number: qualitative; area of interest: qualitative; GPA: qualitative

C)

A researcher wanted to determine whether women with children are more likely to develop anxiety disorders than women without children. She selected a sample of 900 twenty-year old women and followed them for a twenty-year period. At the start of the study, none of the women had children. By the end of the study 53% of the women had at least one child. The level of anxiety of each participant was evaluated at the beginning and at the end of the study and the increase (or decrease) in anxiety was recorded. The researchers analyzed the results to determine whether there was an association between anxiety and having children. A) retrospective; Individuals are asked to look back in time. B) cross-sectional; Information is collected at a specific point in time. C) cohort; Individuals are observed over a long period of time.

C) cohort; Individuals are observed over a long period of time.

A recent study attempted to estimate the proportion of Florida residents who were willing to spend more tax dollars on protecting the Florida beaches from environmental disasters. Thirty-one hundred Florida residents were surveyed. Which of the following is the population used in the study? A) the Florida residents who were willing to spend more tax dollars on protecting the beaches from environmental disasters B) all Florida residents who lived along the beaches C) the 3100 Florida residents surveyed D) all Florida residents

D)


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