statsSuppose the average lion/lioness relationship is normally distributed with a mean number of 90 days and a standard deviation of 25 days. What is the probability that a randomly selected lion’s relationship has lasted for 75 days or fewer? Round to

Ms. Charles picked up 19 items in the grocery store with a mean cost of $3.25. Then she added a pecan pie that costs $20.25. What is the new mean for all 20 items?

$4.10

The average length of a Burmese python captured in the Florida Everglades is 7.3 feet with a standard deviation of .8 feet. If the distribution of Burmese python's heights is normally distributed, what is the Z-score for a Burmese Python that was captured in the Florida everglades and is 6.1 feet long.

-1.5

Suppose a gas station monitors how many bags of ice they sell along with the maximum daily temperature for 100 days. A gas station data analyst plots the data in a scatter plot with temperature, in °F, on the horizontal axis and the number of bags of ice sold on the vertical axis. She calculates a linear correlation coefficient of 𝑟 = 0.8752. The mean temperature is 82.16°F with a standard deviation of 7.41°F. The mean number of ice bags sold is 68.36 with a standard deviation of 22.24.

-147.72

What is the residual for the student who spent 35 hours studying and made a 125 on the test?

-2.44

All bags entering a research facility are screened. Ninety-seven percent of the bags that contain forbidden material trigger an alarm. Fifteen percent of the bags that do not contain forbidden material also trigger the alarm. If 1 out of every 1,000 bags entering the building contains forbidden material, what is the probability that a bag that triggers the alarm will actually contain forbidden material?

.00640

Researchers suggest that 13% of females in Scotland have red hair. Approximately 12% of Scottish people have red hair, and the population is 52.5% female. What is the probability that a randomly chosen member of the Scottish population is a female with red hair?

.068

Suppose that the prevalence of a certain type of nut allergy is 0.21 in the general population. If 100 people randomly chosen from this population are tested for this allergy, what is the probability that exactly 21 of them will have this allergy?

.0975

The probability that a new refrigerator will stop working in less than 2 years is 0.09. The probability that a new refrigerator is damaged during delivery and stops working in less than 2 years is 0.04. The probability that a refrigerator is damaged during delivery is 0.12. Given that a refrigerator is damaged during delivery, what is the probability that it stops working in less than 2 years?

.33

Suppose that a high school marching band has 108 members. Of these 108 band members, 39 are seniors, 23 play the trumpet, and 8 are seniors who play the trumpet. What is the probability that a randomly selected band member is a senior given that he or she plays the trumpet?

.348

The distribution of the amount of a customer's purchase at a grocery store is approximately normal, with mean $45.50 and standard deviation $2.72. Which of the following is closest to the proportion of customer purchase amounts between $46.00 and $56.00 ?

.4270

For flights from Washington Dulles airport in January, there is a 35 percent chance of a flight being delayed because of icy weather. If a flight is delayed because of icy weather, there is a 30 percent chance the flight will also be delayed because of a mechanical problem. If a flight is not delayed because of icy weather, there is a 20 percent chance that it will be delayed because of a mechanical problem. If one flight is selected at random from the airport in January, what is the probability that the flight selected will have at least one of the two types of delays?

.480

What is the probability that a randomly selected tree from this experiment lived more than four years or was left untreated?

.510

The table shows several values of x and their corresponding values of y. Which of the following is closest to the correlation between x and y? Please provide the r value rounded to the nearest hundredth.

.77

A restaurant manager collected data to predict monthly sales for the restaurant from monthly advertising expenses. The model created from the data showed that 36 percent of the variation in monthly sales could be explained by monthly advertising expenses. What was the value of the correlation coefficient?

0.60

A researcher in Florida measured the age (in months) and the length (in inches) of a random sample of adolescent alligators. When the least-squares regression analysis was performed, the correlation was 0.72. Which of the following is the correct way to label the correlation?

0.72

In order to have a well designed experiment, an experiment needs to have which of the following conditions? 1. Subjects must be randomly assigned to treatments. 2. At least two treatment groups or a control group for comparison. 3. Replication.

1, 2, and 3

A sleep time of 13.9 hours per day for a one-week old puppy is at the 15th percentile of the distribution of sleep times for all one-week old puppies. Assuming the distribution is normal with a standard deviation of 1.2 hours, approximately what is the mean sleep time, in hours per day, for one-week old puppies?

15.14

Given the following data, please answer the question below. 18 31 34 35 39 41 42 52 42 77 Which of the following is true?

18 and 77 are outliers.

The weights of 10-ounce bags of a particular brand of potato chips can be modeled by a Normal distribution with mean 𝜇 = 10.22 ounces and standard deviation 𝜎 = 0.05 ounce. Using the empirical rule, about what percent of bags weigh less than 10.12 ounces?

2.50%

Suppose the average lion/lioness relationship is normally distributed with a mean number of 90 days and a standard deviation of 25 days. What is the probability that a randomly selected lion's relationship has lasted for 75 days or fewer? Round to the nearest tenth of a percent.

27.4%

At the beginning of the school year, Mrs. Covidera from Grand Oaks High School asks every student in her classes to fill out a survey that asks for their age, gender, how long they have lived at their current address, their favorite school subject, and whether they plan to go to college after high school. Which of the following best describes the variables that are being measured?

3 categorical variables, 2 quantitative variables

Given the following data, please answer the question below. 11 16 13 31 42 35 38 41 42 53 44 What is the Mean of the data? Please round to the nearest tenth.

33.3

Given the following data, please answer the question below. 11 8 13 31 42 35 37 41 42 55 42 27 46 What is the Median of the data

37

Given the following data, please answer the question below. 11 8 13 31 42 35 37 41 42 55 42 27 46 What is the Median of the data?

37

Math scores on the SAT are normally distributed with a mean of 522 and a standard deviation of 30. What is the SAT math score of a student who score at the 20th percentile?

496.75

Mr. Vader collects health data on many men in each of several large countries. One of the variables measured for each man in the study is his weight in pounds. The following list gives the five-number summary for the weights of adult men in one of the countries. Country B: 125, 160, 220, 280, 340 About what percent of Country B men weigh between 220 and 340 pounds?

50%

If the heights of a population of men are approximately Normally distributed, and the middle 95% have heights between 5'2" and 7'2", what is the standard deviation of the heights in this population?

6 inches

Calculate the mean, 𝜇, of a geometric distribution in which the probability of success is 0.14.

7.14

The average yearly rainfall in Soaksville is approximately Normally distributed with a mean of 125 inches. If the rainfall in Soaksville exceeds 135 inches in 15% of the years, what is the standard deviation?

9.65 inches

There is a linear relationship between the number of chirps made by the striped ground cricket and the air temperature. A least squares fit of some data collected by a biologist gives the model y = 25.2 + 3.3x, where x is the number of chirps per minute and y is the estimated temperature in degrees Fahrenheit. What is the predicted increase in temperature for an increase of 3 chirps per minute?

9.9

A manufacturer makes calculators and claims that their reliability is 92 percent. Reliability is defined to be the proportion of nondefective items that are produced over the long term. If the company's claim is correct, what is the expected number of nondefective calculators in a random sample of 1,000 bulbs?

920

Many colleges require applicants to take a standardized test. Suppose that 10500 students take such a test. Several weeks after the test, Bennett receives his score report: he got a 86, which placed him at the 96th percentile. This means that

96% of the test takers scored the same as or lower than Bennett.

Please select the instance in which the variable described is binomial.

A coin flip has two outcomes: heads or tails. The probability of each outcome is 0.50. The random variable represents the total number of tails recorded in 100 flips of the coin.

The relationship between group size and percent woodland appears to be negative and nonlinear. Which of the following statements explains such a relationship?

As the percent of woodland increases, the number of deer observed in a group decreases quickly at first and then more slowly.

Which of the following is the best description of a positive association between two variables?

As the value of one of the variables increases, the value of the other variable tends to increase.

Which of the following are disjoint events?

Being a Freshman at GOHS and a Senior at ORHS.

The counselors at GOHS would like to streamline the course selection process. They intend to collect data from every student on campus in order to better understand how to implement the new selection process. The counselors will need to utilize which of the following sampling methods?

Census

Conroe ISD is considering offering employees one of two new benefits—one additional day of paid vacation per year or a small increase in pay. A survey will be given to a sample of employees to investigate which benefit is preferred. Since the district is so large, Dr. Null randomly selects three campuses and surveys every employee at that campus. What type of sampling method did Dr. Null use?

Cluster Sample

During the 2020 school year, Conroe ISD has been providing free lunches for all of their students. In order to assess cost, Dr. Null is interested in finding out what percentage of students are getting lunch from the school cafeteria. Since Conroe ISD is such a large district, Dr. Null drives to Conroe High School and samples the first 200 people that enter the cafeteria. What type of sampling method did Dr. Null use?

Convenience Sample

Which of the five labeled points is the most influential with respect to a regression of trade-in value versus miles driven?

E

A botanist found a correlation between the length of an aspen leaf and its surface area to be 0.94. Why does the correlation value of 0.94 not necessarily indicate that a linear model is the most appropriate model for the relationship between length of an aspen leaf and its surface area?

Even with a correlation value of 0.94, it is possible that the relationship could still be better represented by a nonlinear model.

What is the sample space for flipping 2 quarters?

HH, HT, TH, TT

The mean weight of 30 randomly selected apples at Full's Orchard is 182 grams. The standard deviation is 7.8 grams. What does the standard deviation represent?

How far, on average, an individual apple falls from the mean.

If Luke tunes into his favorite radio station at a randomly selected time, there is a 0.10 probability that a commercial will be playing.

If you take a very large random sample of times that Luke tunes into his favorite radio station, about 10% of the time a commercial will be playing.

If Luke tunes into his favorite radio station at a randomly selected time, there is a 0.10 probability that a commercial will be playing. Interpret this probability as a long-run relative frequency.

If you take a very large random sample of times that Luke tunes into his favorite radio station, about 10% of the time a commercial will be playing.

The GOHS Debate Team plans to survey a random sample of 4 local restaurant establishments to determine their interest in participating in a fund raiser for their Team. Use Table D at line 117 to select an SRS of size 4. Angie's MexicanJoe's ItalianBaytown SeafoodLa Palma MexicanaBeto's MexicanManny's BBQ & GrillBurger BoyMcKenzie's BarbequeChick Fil APacific Yard HouseChina DelightPanera BreadDosirak Korean CafeRed Brick PizzeriaEast BuffetVero Italian KitchenFreebirds World BurritoVilla ItaliaHonor CafeWhataburger Which of the following restaurants would not be included in the sample?

Manny's BBQ & Grill

The distribution of random variable A has mean 12 and standard deviation 4. The distribution of random variable B has mean 7 and standard deviation 3. If A and B are independent, what are the mean and standard deviation of the distribution of A − B ?

Mean 5 and standard deviation 5

If a data set is skewed to the right or the left, which measure of center should be used?

Median

Which of the following would change the shape of a distribution? I. Multiplying every number by 3. II. Subtracting 50 to every number.

Neither

Dr. Null is considering allowing high school students to leave campus during lunch to pick up food from nearby restaurants instead of having to eat in their school's cafeteria. He randomly selects 2,000 high school students in the district and sends out a survey to get their opinion on this proposal. 800 of the 2,000 surveys are returned. What type of bias will be present in this sample?

Nonresponse Bias

The weight of oranges chosen at random from a farmer's orchard follows a Normal distribution with mean 𝜇 = 11 ounces and standard deviation 𝜎 = 1.5 ounces. Suppose we pick 5 oranges at random from the orchard and find their total weight 𝑇.

Normal, with mean 55 ounces and standard deviation 3.35 ounces.

Dr. Povich is concerned about the amount of time GOHS band students spend in the sun. He wants to purchase suntan lotion for the entire band and is trying to decide between two different lotions. A randomized block design will be used in an experiment to compare two lotions that protect GOHS band students from getting sunburned. Which of the following should guide the formation of the blocks?

Participants within each block should be as similar as possible with respect to how easily they get sunburned.

Which of the following is the best description of the relationship displayed in the scatterplot?

Positive, linear, and strong

Dr. Povich conducted a survey by sampling 200 GOHS students to see what percentage of students had already paid to take their AP test. 78% of the respondents stated they had paid for their AP tests. However, data shows that only 42% of students had paid for their AP tests. Which of the following bias is most likely to have occurred.

Response bias

During the 2020 school year, Conroe ISD has been providing free lunches for all of their students. In order to assess cost, Dr. Null is interested in finding out what percentage of students are getting lunch from the school cafeteria. Dr Null assigns every student in the district a number and randomly selects 1,000 students using a random number generator. What type of sampling method did Dr. Null use?

Simple Random Sample

Please classify the histogram.

Skewed to the left

During the 2020 school year, Conroe ISD has been providing free lunches for all of their students. In order to assess cost, Dr. Null is interested in finding out what percentage of students are getting lunch from the school cafeteria. Dr. Null believes that the percentage of students eating lunch from the school cafeteria will be different between the elementary, intermediate, junior high, and high schools. Therefore, Dr. Null decides to randomly select 250 elementary students, 250 intermediate students, 250 junior high students, and 250 high school students. What type of sampling method did Dr. Null use?

Stratified Sample

A family would like to build a linear regression equation to predict the amount of grain harvested per acre of land on their farm. They subdivide their land into several smaller plots of land for testing and would like to select an explanatory variable they can control. Which of the following is an appropriate explanatory variable that the family could use to create a linear regression equation?

The amount of fertilizer applied to each plot of land

Dr. Povich wants to estimate the number of students who are tardy to 1st period. He reviews the cameras in the school to count how many students showed up late to first period. What type of investigation is being conducted by Dr. Povich?

The investigation is an observational study because treatments are not imposed.

The random variable R has mean 8 and standard deviation 2.5. The random variable T is defined as T = 6 + 2R. What are the mean and standard deviation of T?

The mean is 22, and the standard deviation is 5.

If a distribution is skewed to the right, which of the following is true?

The mean must be greater than the median.

Given the following data, please answer the question below. 22 16 13 31 42 35 39 41 42 65 42 27 42 What is the range of the data?

The range is 52.

Professor Aang collected data on the scores from the Unit 3 Review and the scores from the Unit 3 test. The professor computed a correlation of 0.72 between the two variables. What information does the correlation provide about the relationship between the scores on the review and the scores on the test?

The students with higher scores on the review are associated with higher scores on the test.

Identify the type of sampling bias guaranteed to occur in the following sampling scheme, based on the information provided. A survey asks the question, "If you found out that vehicles with more than 2 axles pollute our air three times as much as a passenger vehicle, would you support legislation that requires an annual Clean Air Tax on all non-passenger vehicles?

Wording of the Question

Suppose a researcher wants to estimate the average rainfall in Montgomery County. She already has a data set that contains the unique identification number and location for each rain gauge in the county. She decides to estimate the average rainfall from a sample of rain gauges. She identifies a method for sampling the rain gauges. She divides the county into 15 equal regions. She then selects five of the regions at random and forms her sample from the rain gauges in those regions. Which sampling method did the researcher utilize?

cluster sample