STATS EXAM
It's a student scored 75 points on a test for the mean score was 83.5 and a standard deviation was 6.1. The students Z score is
-1.39
I wanna see scores that have 85% of the area between -z and z
-1.44 and 1.44
A sample of the manager of a sports shops inventory finds that he sells a mean of 104 baseball caps per week with a standard deviation of 14 what would the standard score be if 69 cops were sold in a given week?
-2.50
You draw three cards from a deck of 52 cards and replace the card after it is drawn. What is the probability of getting a spade, a red card and then an ace in that order?
.0096
The probability that DeAndre has to work overtime and it rains is 0.028. DeAndre here's the weather forecast, and there's a 50% chance of rain. Find the probability that he will have to work overtime, given it rains.
.056
Probability bird probability fish probability bird and fish probability N bird probability U fish
.2 .3 .06 .94 .44
Number 10 on unit three test. If a student is selected at random, what is the probability the student is a female and a junior?
.241
Number seven on unit three. If a person is selected at random, what is the probability that the person is an instructor or a professor?
.524
Geometry problem P (.5< X < 3) P (X < 2.5) P (.5 < X < 1.5)
.6125 .7 .3
If P (A) = .33 what is P (not A)
.670
Number eight on unit three. The person is selected at random, what is the probability here she is not a professor?
.683
A box contains five blue marbles, three red and six white marbles. If four marbles are drawn, without replacement, what is the probability all four are red?
0
Suppose it is known that 80% of the people exposed to the flu virus will contract the flu. Out of a family of six exposed to the virus, what is the probability that no more than two will contract the flu?
0.0170
Mr. Rose Econ class was taking a 10 question test with a choices, we're only one answer choice exists on each question. If a student took the test and they guessed on all of the questions, what is the probability that the student will get exactly 4 questions correct?
0.023
If 1.5% of the bolts made by an automotive factory are defective, what is the probability that in a shipment of 200 bolts, there are six defective bolts?
0.05
Suppose it is known that 80% of the people exposed to the flu virus will contract the flu. Out of a family of six exposed to the virus, what is the standard deviation?
0.98
The sum of all the probabilities of the events in the sample space is equal to
1
I should be the value of Z used in a 93% confidence interval
1.81
#24 on unit 3 check on phone
1/12 41/48 9/10 1/6 20/31
Find the probability of getting a number greater than four when a die is rolled one time
1/3 D
15 students were given a test. What is the main score for this class? 10 9 12 11 8 15 9 7 8 12 10 11 8 7 15
10.1
Mr. Bo wants to comprise a team of boys and girls to start a math club. He has 24 boys volunteer and 17 girls. He hast to take 10 students to compete, how many ways can he form his team?
1121099408
What is the class with if the class limits are 225 through 236
12
The average cost of repairing laptop is $120 with a standard deviation of $10.50. The costs are normally distributed. If 15% of the costs are considered excessive, find the cost in dollars that would be considered excessive.
130.88
Assume that gas prices are normally distributed with a mean of $2.15 per gallon and a standard deviation of $.12 per gallon. What price would represent the 80th percentile?
2.25
Suppose 135 students are surveyed about their favorite ice cream flavors. Draw a van diagram in the box for the following statements and then use it to answer the questions. 63 like chocolate, 61 like Carmel, 53 like vanilla, 28 like caramel and vanilla, 31 like chocolate and caramel, 22 like chocolate and vanilla, 15 like all three flavors.
25, 16, 17, 7, 15, 13, 18, 24
Mr. Val wants to comprise a team of boys and girls to start a math club. He has 24 boys volunteer and 17 girls. They are doing speed runs of math which consist of a most two boys in a group of five. How many ways can he form this group?
250988
Assume that the salaries of elementary school teachers in the United States are normally distributed with a mean of 33,000 and a standard deviation of 4000. What is the cut off salary for the teachers in the bottom 15%
28,854.27
The lifetime of a certain light bulb is normally distributed with a mean of 240 hours in a standard deviation of 25 hours. How long will the lightbulbs last in order to be in the top 5%?
281.12
In a four-point grading system and a corresponds to four points because sponsor three points see correspondence to two points and so forth. SMS or Christina got an a in a foursome master our course, and also got a three semesters our course. She got a B in a five semesters our course and a C in a two semesters our course. A GPA is computer as a weighted average using the number of some extra hours as weights in the number of points correspondence to the grade as the data. Compute Christina GPA for the semester.
3.36
Unit 5 #24
335.51
Mr. though wants to comprise a team of boys and girls to start a math club. He has 24 boys volunteer and 17 girls. He needs to have seven girls and three boys in his next competition. How many ways can he form this team?
39362752
What are the outliers 506 511 517 514 400 521
400
An eight sided die, numbered 1 to 8, is rolled. Find the probability that the role results in an even number or a number greater than six.
5/8
12.5- 27.5 F:6 27.5-42.5 F:3 42.5-57.5 F:5 57.5-72.5 F:8 72.5-87.5 F:6 87.5-102.5 F:2
55.5
What is the variance 10 9 12 11 8 15 9 7 8 12 10 11 8 7 15
6.1
A quality control expert wants to estimate the proportion of defective components that are being manufactured by his company. A sample of 300 components showed that 20 were defective. How large a sample is needed to estimate the true proportion of defective components to within 2.5% point within 99% confidence
661
A sample of the manager of a sport shop inventory finds that he sells a mean of 104 baseball caps per week with a standard deviation of 14 find an interval centered around the mean in which we can expect to find 75% of the data
76-132
A student receives test scores of 72, 75, and 81. The students final exam score is 78 and homework score 76. Each test is worth 20% of the final grade, the final exam is 25% of the final grade, and the homework grade is 15% of the final grade. What is the students mean score in the class?
76.5
Assume you want to create a histogram for a set of data where the largest data value is 65 and the smallest data values 14 if you were to group this data into seven classes what should the class width be?
8.0
In a distribution of 200 values the -50 and the standard deviation is five. Assuming you distribution is normal, what percent of your values will fall between 45 and 65?
83.85
1000 lightbulbs have an average lifetime of 2000 hours with a standard deviation of 25 hours. How many lightbulbs are expected to last between 1925 and 2075 hours?
889
In a distribution of 200 values, the mean is 50 in the standard deviation is five. Assuming the distribution is normal what percent of the data will fall between 40 and 60
95%
Freshman SAT scores of the Dowd Institute of technology have a sample mean of 1290 with a standard deviation of 150. What to SAT scores would I expect 95% of the freshman class to fall between?
990-1590
Which box that has a five number summary of five, seven, eight, 12, 13 and interquartile range of five?
A
Which of the following distributions is a probability distribution?
A (PX = 1)
A study was conducted on geese and found that the mean migrating distance was 1200 km with a standard deviation of 230 km. If a sample size of 15 geese are tracked and the data is collected find the probabilities: A use the central limit theorem, find the probability that the sample mean is between 1150 and 1265 B greater than 1300 km C less than 1100 km
A .6633 b. .0461 C. .0461
In a large bag of marbles, 25% of them are red. A child chooses for marbles from this bag. If the child chooses the marble at random, what is the chance that the child gets exactly 3 red marbles.
A 0.047
The average gas mileage of a certain model car is 28.0 miles per gallon. If the gas mileage is are normally distributed with a standard deviation of 0.45 miles per gallon, find the probability that a car has gas mileage of between 27.8 and 28.2 miles per gallon.
A 0.343
X is normally distributed random variable with a mean of 9.0 and a standard deviation of 3.0. Find the value X such that P(x>x) is equal to 0.86
A 12.24
There are three blue balls, five red balls, and four white balls in a bag of balls. If a person selects two of the bars, what is the probability that the second one is blue given the first one was white?
A 3/11
Number 15 on unit three. In a recent study, the following responses were obtained to the question, do you favor recycling in your neighborhood? If a response is picked out random, what is the probability that it came from a male or that it indicated no opinion regarding recycling?
A 3/5
Is this soda comes in two varieties, regular diet. If a researcher has four boxes of each, how many ways can he select two boxes of each for a quality control test?
A 36
In the happy Hilton health home, 10% of the residents play shuffleboard, 35% of the residents play poker, and 10% of the residents garden. 5% of the residents play poker and garden then find the probability that a resident plays poker, given that they also garden.
A 50%
GRAPH: A. what height represents Q1? B. what height represents Q2? C. What height represents Q3? D. what is the IQR?
A 67.5 B 69.5 C 71.5 D 4
Find the variance for the values of N and P when the conditions for the binomial distribution's are met. N =500 P = .75
A 93.75
Which of the following are important in the design of an experiment? A. Control of potential confounding B. randomizing in assigning subjects to different treatments C. Replication of the experiment using sufficient numbers of subjects
A B and C
Assume the given distributions are normal. A factory dumps an average of 2.43 tons of pollutants into a river every week. If the standard deviation is 0.88 times, what is the probability that in a week more than 3 tons are dumped?
A P (Z> 3 - 2.43/0.88)
Archer estimates that she can hit her target 80% of the time. Assuming that each of her throws is independent, which of the following probability statements is correct?
A P(4 hits in her next 6 throws) (6/4) (.20)^2 (.80)^4
When two events are independent, the probability of both occurring is
A P(A and B0 = P(A) X P(B)
If a normal distribution has a mean of 20 and a standard deviation of 10 then
A the median is 20 and the mode is 20
Number 26 on unit four test
A. .1606 B. .4457 C. .5314 D. .682
Men's shirt sizes question determined by their neck size. A. What proportion of customers will find that the retailer does not carry any shirts in their sizes? B. what is the proportion of men who shirt sizes is medium
A. 1-normcdf(14,18,15.7,0.7) =.0081 B. normcdf(15,16,15.7,0.7) = .507
The mean score on a national engineering aptitude test is 450 and the 90th percentile is 680. A. what percent of those who took the test has scores at or above 680? B. what percent of those who took the test had scores between 450 and 680?
A. 10% scored above 680 B. 40%
#28 on unit three test
A. 31/80 B. 45/80 C. 67/80 D. 3/80 E. 7/40
The average grade on this test in the previous years is an 86 with a standard deviation of four A. what is the scores for the middle 95%? B. what percent has a score more than 94? C. What percent scores between 74 and 94? D. what percent has the score more than 98?
A. 78-94 B. 2.3% C. 97.5% D. .135%
Tell what types of bias is possible with each scenario. Voluntary, response, non-response, wording or convenience. A. Mr. Vo ask the opinion of the first five students that enter into the classroom. B. Mr. Vo hands each student a survey and ask them to fill it in. He receives three surveys back. C. Mr. Vo put surveys on the front table. 15 students pick up the survey, fills it out and turns it in. D. Mr Vo is asked to fill out a survey about his recent hospital visit. The questions include medical terminology that he is unable to pronounce and are not too sure what they mean.
A. Convenience B. Nonresponse C. Voluntary D. Wording
Select the most appropriate probability model for the given situation's. A. what is the probability that the first kiss occurs on the third day if the probability of a case occurring on any given day is 46% B. what is the probability that a family with five children will have all girls? C. At a certain intersection, there is an average of two accidents per week. What is the probability that at least five accidents will occur in the next two weeks.? D. what is the probability that a shipment of 100 fruits will have no more than six rotten fruits if the probability that anyone through is rotten is .04%
A. Geometric B. Binomial C. Poisson D. Binomial
RHHS: 170, 165, 140, 188, 195 Clover: 144, 177, 215 225, 197 Fort Mill: 166, 175, 196, 206, 219 A. Find the means and standard deviation of the weights for all three high schools B. which team has the most variation and weights?
A. RHHS- mean: 171.6 STD: 19.29 Clover- Mean: 191.6 STD: 28.88 Fort Mill- Mean: 192.4 STD: 19.52 B. Clover had the most variation because the standard deviation was the highest.
Suppose there are 200 teachers at our HHS. Mr. all wants to perform a survey to find information about teachers opinions of teaching three out of the four blocks. He comes to stats honors for help. A. explain how to select 20 teachers using an SRS method B. explain how to select 20 teachers using stratified random sample. C. Explain how to use a systematic random sample to select the 20 teachers. D. he decides to stop the first 20 teachers in the parking lot. Explain why this would not be a good idea.
A. give all 200 teachers a number one through 200 then randomly generate a number 1 through 200, 20 times. After you have 20 random numbers, ask the 20 teachers their opinion. B. divide the 200 teachers in a different groups, then take an SRS from each group C. Find a roster with all 200 of the teachers names on it. Then choose every 10th teacher on the roster. D. stopping the first 20 teachers in the parking lot is not a good idea because it would produce bias and wouldn't give him an accurate representation on how the teachers felt.
A camera store placed an ad in the newspaper showing a digital cameras for sale the ad says, our digital cameras average $155. The prices of the digital camera are $450, $500, $399, $155, $499, $525, $155, and $490. A. find the mean, median, and mode for the prices. B. which measure is the store using in its ad? Why did they choose this measure? C. As a consumer which measure would you want to see advertised?
A. mean equals 396.62, median equals 470, mode equals 155. B. the store chose to use the mode as the measure. They chose this measure because it is the cheapest in the value of two of the eight cameras. C. As a consumer, I would like to see the main captured. That way I am able to tell what the average price of a camera is.
WRITE ON CARD Find the probability that the number of visitors will be between 5000 and 18,750 Find the probability that the number of visitors will be less than 13,250
A.97% B. 35%
Nicolas works for a hard-core rock music label, and he determines which artists get a record deal. The probability someone receives a record deal is .32 from Nicolas. Last week, necklace went to 15 auditions. A. What is the probability that he will sign exactly 5 artist? B. What is the probability he will sign at least for artists? C. What is the probability he will sign fewer than 11 but at least two artist?
A= .2130 B= .758 C= .9740
Mr. valve on the probability of making an a on this test is .45. A find the probability that the first 80 grades is the second test B find the probability that the first A is graded before the third paper
A= .2475 B= .6975
If P (A)= .5, P(B) = .6 and P (A and B) = .85 then what is A. P (A and B) B. P(A|B) C.P (B|A)
A= .3 B= .5 C= .6
A firm tested the durability of four different types of tires by having four Toyotas each randomly equipped with one of the types of tires. In a similar fashion, for Hondas were used, each randomly equipped with one of the tires tight. And I like manner, four forwards were each randomly outfitted with one of the four tire brands. Then each of the 12 cars ran over a test track until the tires showed signs of serious wear. At that point the average milage of the three cars using one type of tire was compared to the average mileage of the three cars using the second type of tires, and so on. This design is:
An example of a randomized block design
What is the difference between observational study and an experiment?
An observational study you are just observing what happens and not doing anything about it such as taking a radar gun on I 77 and checking how many car speed. In an experiment, a treatment is imposed and data can be calculated and recorded.
Income per household in a certain state is normally distributed with a mean of $9500 and a standard deviation of $1750. The middle 95% of incomes are between what two values?
B $6070 and $12,930
Assume that the probability that a baseball player will hit in any one at bat is .375. Which expression will yield the probability that his first hit will next occur on his fifth at bat?
B (.625) ^4 (.375)
Number 18 on unit three. Below are a list of the numbers of engineers in various fields by sex. Choose one engineer at random find P parentheses (electrical/male)
B 0.215
In a standard normal distribution, what Z value corresponds to 17% of the data between the mean and the Z value?
B 0.44
Siri normal distribution with a mean of four and a standard deviation of two, the value five has a Z value of
B 0.5
A business has seven locations to choose from and wishes to rank only the top three locations. How many different ways can this be done?
B 210
In order to have the standard error of the mean be 11, one would need to take how many samples from a normally distributed population with a standard deviation of 55.
B 25
For a normal distribution curve with a mean 15 and a standard deviation of three, which range of the variable defines an area under the curve corresponding to a probability of approximately 68%
B from 12 to 18
Find the probability P(Z> -.54) using the standard normal distribution
B. 0.7054
Suppose the average score of the national test is 500 with a standard deviation of 100. If each scores increased by 25% what are the new mean in new standard deviation?
B. 525, 100
Which of the following are true statements? I. all three have the same range II. All have the same interquartile range III. The difference in the medians between the first and third distributions is equal to the interquartile range of the second distribution.
B. I and III
Which of the following statements is false? Unit 5 #21
C
How many different ways can a teacher select five students from the class of 19 students to each perform a different classroom task?
C 1,395,360
A furniture manufacturer offers bookcases and three different sizes and for different colors. If every color is available in every size, then the total number of different bookcases is
C 12
A sample of 35 different payroll departments found that employees worked an average of 240.6 days a year if the population standard deviation is 18.8 days, find a 90% confidence interval for the average number of days worked by all employees who are paid through payroll department
C 235.4, 245.8
Each of a students wishes to buy a particular textbook, but only five textbooks are available. How could one expressed the number of ways those textbooks could be distributed among the students?
C 85C
Consider the following to normal curves. Which has the larger mean in which has the larger standard deviation?
C larger mean B; larger standard deviation a
The term ZC (o/n) is
C maximum error of estimate
Find the area under the standard normal distribution curve between Z= -2.05 and Z= 2.05
C. 0.9596
The 1992 and AEP trial state assessment calculated a state by state average mathematics proficiency score for students in the eighth grade there's nothing box bar is below. Which of the following statements are true? I. the state score to 73 has a percentile rank of 75 II. The mean state score is 270 III. The lowest state score is 245
C. I and III
A study of the salaries of all the college professors at Winthrop University
Census
A researcher wants to determine what percent of first graders still believe in the tooth fairy. He decides to use Ms. Wilson's first graders at Independence Elementary as his sample. The sampling technique being used by the researcher is: (Hint: There are 3 1st grade teachers)
Cluster
State if the following is continuous or discrete The amount of time it takes a student to drive to school The number of kangaroos in a various wildlife refugees in Australia The amount of time a whale can hold its breath The temperature in degrees Fahrenheit on July 4 The number of text messages you send Your shoe size
Continuous, discrete, continuous, continuous, discreet, discreet
The average length of crocodiles in a swamp is 12 feet. If the links are normally distributed with a standard deviation of 1.9 feet, find the probability that a crocodile is more than 11.5 feet long
D 0.60
A certain type of battery has a .5% failure rate. Find the probability that a shipment of 1000 batteries has more than two defective batteries.
D 0.875
A coin is tossed five times. Find the probability that all five tosses are tales
D 1/32
A box contains blue chips and red chips. A persons Alex to chips without replacement. If the probability of selecting a blue chip and a red ship is 1÷4 and the probability of selecting a blue chip on the first shot is 5÷16 find the probability of selecting the red chip on the second draw, given that the first chips like it was a blue check.
D 4/5
Which choice is another term that can be used to describe normal distribution?
D Bell curve
STEM PLOT Which of the following are true statements? I the distributions have the same mean II the distributions have the same range III the distribution of the same variance
D. II and III
During memorial day 20 people were killed in car accidents
Descriptive
Of the 30 nurses in pediatrics, 20 work during the day and 10 work at night
Descriptive
The collection, organization, summarization and presentation of data is called
Descriptive statistics
An electronic product takes an average of 3.4 hours to move through an assembly line. If the time is normally distributed with a standard deviation of 0.5 hour, what is the probability that an item will take between three and four hours to go through the line?
E .6730
Which of the five choices below describes a feature that is true about stem and leaf displays
Each data value is broken into two parts
A child gets 20 heads out of 30 tosses of a coin. If he declared the chance of getting a head with that coin or two out of three, that would be an example of blank probability
Empirical
Number 19 on unit four test. A doctor developed a test to measure anxiety levels. The possible scores are zero through six with six indicating the highest levels of anxiety. She administered the test to 2000 volunteers between the ages of 21 and 35. Using the table below find the expected score, variance and standard deviation.
Expected score is 3.0085; variance is 2.051; standard deviation is 1.432
Mr. Bo's math class has 60 students if there is a 15% absentee rate per day, find expected value and standard deviation of number of students who will be absent from the class.
Expected value is 9; variance is 7.65; and standard deviation is 2.766
Determining the probability of an event all possible answers can range from 0 to 100
False
Hypothesis testing is the highest level of measurement
False
Napping and exercising or not mutually exclusive events
False
Statistics is divided into two main areas called descriptive and hypothetical statistics
False
The subject matter that a college professor teaches would be an example of ordinal level data
False
When rolling two dice the sample space is 12
False
When the outcome of event a does not affect the probability of the outcome of a subsequent event be, then the events are said to be dependent.
False
Which of the following is an area of inferential statistics
Generalizing from samples to populations
Based on past figures, it is predicted that only 52% of registered voters will vote in the next election
Inferential
Which of the following is an area where statistics is used?
Insurance, medicine, gambling (All)
The size of the box in a box plot shows the _____ of the data set
Interquartile range
SAT scores at rock Hill high school
Interval
The hair color of student athletes
Nominal
What is the level of measurement that consists of classifying data into mutually exclusive categories in which no order or ranking can be imposed
Nominal level
Gold silver and bronze medals at the Olympics
Ordinal
Select the most appropriate term from the choices below. This tool for visually organizing data identifies the frequency or relative frequency of events or categories and decreasing order of occurrence
Pareto Chart
A parameter is a characteristic or measure obtained by using all of the data values for a
Population
A persons blood type would be an example of what type of data
Qualitative
The favorite flavors of ice cream for first graders
Qualitative
The religious affiliations of students at rock Hill high school
Qualitative
The number of pages typed by a secretary
Quantitative
Miss Laurens wants to do a survey on how many freshman at her school I've tried drugs. There are 300 freshmen at her school, so she assigns each student a number puts them in a box shakes them up and draws 40 different numbers.
Random
A study of 100 members of a larger labor union were polled regarding a proposed new contract
Sampling
A study where you would like to determine the chance of getting three girls and a family of three children
Simulation
This tool for visually organizing quantitative data is useful for detecting patterns and extreme values by organizing and grouping the data but allows one to recover the original data if desired.
Stem and leaf
A company with offices in five different countries is interested in estimating proportion of its employees in favor of banning smoking on the office premises. It is known that the views of people from different countries on issues like smoking tend to vary due to the influence of different social structures. Which of the following is an appropriate sampling technique to use in the situation and why?
Stratified sample, because the population is divided into five strata - namely the five offices in the five different countries
The statement, the probability that a certain sports team will win its next game is about 60%, is an example of
Subjective
A reporter interviews every fourth person
Systematic
Samantha wants to pull her classmates on their favorite Netflix show. She puts her classmates names in alphabetical order and then picks every third name. What is samantha sampling technique called?
Systematic
Which describes a feature that is true about bar graphs?
The bars in the graph can be vertical or horizontal
Which describes a feature that is true about histograms?
The bars in the graph touch
Which describes a feature that is true about time plots?
The intervals on the horizontal axis represent equal units of time
Schools in York County want to add a special tax to the ballot to increase teacher pay. They surveyed residents with the following question: what do you support a special tax that will cost taxpayers 50 million over the next 20 years to raise teacher pay? What is the potential source of bias?
The potential source of bias from the scenario is wording bias. Obviously no one wants their taxes to go up and buy saying that it will cost taxpayers 50 million over the next 20 years you are trying to sway someone in a certain direction
Theater versus art major
The theater major has a higher score than the art major
In a recent report, a group of scientist claim that Americans are consuming an excessive amount of selenium in their diets. The national science foundation has started that the safe upper limit is 200 µg per day. In order to determine the extent of the problem in Plano, researchers divided the town into five regions based on economic levels and drew random samples of household from each region. They then interviewed in the door at the residence and measure their daily consumption of selenium. Identify sampling method and one possible source of bias.
The type of sampling method used in this scenario is stratified sampling. One possible source of bias could be response bias since some adults may not even know how many micrograms of selenium they are taking a day.
What are the stems for the data set 62, 71, 67, 53, 66, 35, 34, 45
Three, four, five, six, seven
One way to obtain a random sample is to use random numbers
True
The variable gender would be an example of a qualitative variable
True
Assume M equals 95 and standard deviation equals five Z= 2.1 Z= -1.36 Z= -.54 Z= .40 Z= .01
X= 105.5 88.2 92.3 97 95.05
Termine whether the following can be reduced to a binomial experiment. Asking a number of people whether they were glasses or not Choosing the number of toppings for your pizza Asking students how many electives they are taking Asking a number of people if they have a pet or not
Yes, no, no, yes
