The Physicians' Health Study, a large medical experiment involving 22,000 male physicians, attempted to determine whether aspirin could help prevent heart attacks. In this study, one group of about 11,000 physicians took an aspirin every other day, while
E
John wants to determine how age and gender are related to political party preference in his town. Voter registration lists are stratified by gender and age group. John selects a simple random sample of 50 men from the 20 to 29 age group and records their
E
Under which of the following conditions is it preferable to use stratified random sampling rather than simple random sampling?
A) The population can be divided into a large number of strata so that each stratum contains only a few individuals.
B) The popu
C
In one study on the effect of niacin on cholesterol level, 100 subjects who acknowledged being long-time niacin takers had their cholesterol levels compared with those of 100 people who had never taken niacin. In a second study, 50 subjects were randomly
B
. George and Michelle each claimed to have the better recipe for chocolate chip
cookies. They decided to conduct a study to determine whose cookies were
really better. They each baked a batch of cookies using their own recipe. George
asked a random sample
D
The director of a fitness center wants to examine the effects of two exercise classes (spinning and
aerobics) on body fat percentage. A six-week spinning class and a six-week aerobics class are offered at
the same time and on the same days, so that a pers
C
The box plots shown above summarize two data sets, I and II. Based on the box plots, which of the following statements about these two data sets CANNOT be justified?
A) The range of data set I is equal to the range of data set II
B) The interquartile rang
D
The table below shows the sample size, the mean, and the median for two samples of measurements. What is the median for the combined sample of 47 measurements?
too difficult to write out lbeheheh
It cannot be determined from the information given.
A local real estate magazine used the median instead of the mean when it reported the SAT score of the average student who attends NBHS. A graphical display of SAT scores of students who attend Groveland High School indicated that the data were strongly s
A
The histogram below displays the time in minutes needed for each chimpanzee in a sample of 26 to complete a simple navigational task
Too lazy bnlerhgw97ehw9he
D) Left end point at 0, median at 20, Q3 at 40
Determine the smallest weekly earnings of a child that is considered an outlier.
NO ANSWER CHOICES
$5.00
Ninety percent of the people who have a particular disease will have a positive result on a given diagnostic test. Ninety percent of the people who do not have the disease will have a negative result on this test. If 5 percent of a certain population has
D
When two fair dice are rolled simultaneously, what is the probability of getting a sum of 7 given that the first die rolled is an odd number?
A) 1/12
B) 1/9
C) 1/6
D) 1/2
E) 1/4
C
At a certain high school, all students who take AP Psychology also take AP Statistics. From past records, the probability that a student gets a 5 in AP Psychology is one- fourth. The probability a student gets a 5 on the AP Statistics exam is one-seventh.
E
Suppose A and B are events with the given probabilities. P(A) = .62, P(B) = .44 and P(A^B) = .31 = .31. Which of the following conclusions can be drawn from the data?
A) P(A or B) = .75
B) A and B are mutually exclusive events
C) A and B are independent e
A
The graph below displays the relative frequency distribution for X, the total number of dogs and cats owned per household ...
A) .170
B) .017
C) .790
D) .600
E) .260
A
A manufacturer makes lightbulbs and claims that their reliability is 98 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 nond
980
The number of sweatshirts, X, a tendon sells daily has the following probability distribution.
If each sweatshirt sells for $25, what is the expected daily total dollar amount taken in by the vendon from the sale of sweatshirts?
A) $5.00
B) $7.60
C) $35.5
D
In a carnival game, a person can win a prize by guessing which one of 5 identical boxes contains the prize. After each guess, if the prize has been won, a new prize is randomly placed in one of the 5 boxes. If a person makes 4 guesses, what is the probabi
(4 choose 2) (.2)^2 (.8)^8
In a carnival game, a person can win a prize by guessing which one of 5 identical boxes contains the prize. Which of the following describes the sampling distribution of x bar?
B (1 = 1/9, 1.5 = 2/9, 2 = 1/3, 2.5 = 2/5, 3 = 1/9)
The probability of obtaining a head when a certain coin is flipped is about 0.65. What is the probability that heads would be obtained 15 or fewer times when this coin is flipped 25 times?
a. 0.14
b. 0.37
c. 0.39
d. 0.60
e. 0.65
B
For a set of values, suppose the mean is 10 and the standard deviation is 2. If each value is multiplied by 9, what will be the mean and the standard deviations or this new set of values?
A) Mean 10; std 2
B) Mean 10; std 18
C) Mean 90; std 2
D) Mean 90;
E
The number of points, X, scored in a game has the probability distribution below.
A) 0
B) 1
C) 2
D) 3
E) 4
C
As a promotional gimmick, a cereal manufacturer packages boxes of cereal with CD-ROM's of popular games.
A) (5 choose 3)
B) (5 choose 3)
C) (5 choose 1)
D) (.8)^2(.2)
E) (.2)^2(.8)
D
A certain type of remote-control car has a fully charged battery at the time of purchase. The distribution of running times of cars of this type, before they require recharging of the battery for the first time after its period of initial use, is approxim
A
A researcher interested in the age at which women are having their first child surveyed women having at least one child and found an approximately normal distribution with a mean age of 27.3 and a standard deviation of 5.4. Approx .95 of the women has the
B
Polly takes three standardized tests. She scores 600 on all three. Using standard scores, rank her performance on the three tests from best to worst if hte means and standard deviations are as follows.
A) I, II, and III
B) II,< II, and I
C) I, III, and II
D
The population {2,3,5,7} has mean mu= 4.25 and standard deviation 1.92. When sampling with replacement, there are 16 different possible ordered samples of size 2 that can be selected from this population. The mean of each of these 16 samples is computed.
B
The graph of two sampling distributions of a sample mean from the same random variable for samples of two different sizes are shown below. Which of the following statements must be true about the sample sizes?
A) The sample size of I is less than the samp
B
Five estimators for a parameter are being evaluated. The true value of the parameter is 0.Simulations of 100 random samples, each of sizen, are drawn from the population. For each simulatedsample, the five estimates are computed. The histograms below disp
B
To check the effect of cold temperature on the elasticity of two brands of rubber bands, one box of Brand A and one box of Brand B rubber bands are tested. Ten bands from the Brand A box are placed in a freezer for two hours and ten bands from the Brand B
D
A high school statistics class wants to conduct a survey to determine what percentage of students in the school would be willing to pay a fee for participating in after-school activities. Twenty students are randomly selected from each of the freshmen, so
D
Researchers are trying to estimate the amount of exercise that US residents get each week. They randomly sample 1,000 patrons at Gold's Gyms around the nation and ask each one to fill out an anonymous questionnaire. What is the major problem with this stu
A
A new medication has been developed to treat sleep-onset insomnia (difficulty in falling asleep). Researchers want to compare this drug to a drug that has been used in the past by comparing the length of time it takes subjects to fall asleep. Of the follo
E
A researcher wishes to test a new drug developed to treat hypertension (high blood pressure). A group of 40 hypertensive men and 60 hypertensive women is to be used. The experimenter randomly assigns 20 of the men and 30 of the women to the placebo and as
B
The buyer for an electronics store wants to estimate the proportion of defective wireless game controllers in a shipment of 5,000 controllers from the store's primary supplier. The shipment consists of 200 boxes each containing 25 controllers. The buyer n
B
When the drug tamoxifen was first introduced to treat breast cancer, there was concern that it would cause osteoporosis as a side effect. To test this concern, cancer subjects were randomly selected and given tamoxifen, and their bone density was measured
C
The box plots below summarize two data sets, A and B.
Set A) Min- 10, Q1- 20, M- 30, Q3- 38, Max- 47
Set B) Min- 13, Q1- 22, M- 28, Q3- 38, Max- 44
Which of the following must be true?
I. Set A contains more data than Set B.
II. The box of Set A contains
B
The figure below shows a cumulative relative frequency histogram of 40 scores on a test given in an AP Statistics Class. Which of the following conclusions can be made from the graph?
(graph is cumulative percent, range of 30 to 100. )
A. There is greater
A
The statistics below provide summary of the distribution of heights, in inches, for a simple random sample of 200 young children.
Mean: 46 inches
Median: 45 inches
Standard Deviation: 3 inches
First Quartile: 43 inches
Third Quartile: 48 inches
About 100
C
Jana collected data on the amount of time in minutes each person in a large sample of customers spent in a classic car museum. While gathering her data, Jana decided to categorize each customer by his or her gender as well. She then generated the parallel
E
A random sample of 25 households from NBISD were surveyed. In this survey, data were collected on the age of the youngest child living in each household. The histogram below displays the data collected in the survey.
Graph is frequency histogram.
Interval
D
The back to back stem and leaf plot shown below can be used to compare the number of hours students at a local university spent studying. A random sample of chemical engineering students was selected and each student was asked the number of hours they spe
C
An experiment has three mutually exclusive outcomes, A, B, and C. If P(A) = .12, P(B)= .61, and P(C) = .27, which of the following must be true?
I. A and C are independent
II. P(A^B)=0
III. P(B or C) = P(B) + P(C)
A. I only
B. I and II only
C. I and III o
D
Suppose A and B are events in a sample space with P(A) = .80 and P(B|A)= .50. Then P( A and B) = ________?
A. 0.3
B. 0.4
C. 0.625
D. 0.8
E. 1
B
Two friends Tom and Janice, have cars in desperate need of repair. On any given day, the probability that Tom's car will break down is 0.28, and the probability that Janice's car will break down is 0.67 since it is older than Tom's. If Tom and Janice's ca
C
Joe and Matthew plan to visit a bookstore. Based on their previous visits to this bookstore, the probability distributions of the number of books they will buy are given below.
Number of books
Joe will buy
0: 0.5, 1: 0.25, 2: 0.25
Matthew will buy
0: 0.25
B
Home pregnancy tests have grown in popularity. Research shows that only 30% of those using a particular kit are actually pregnant. When a pregnant woman uses the kit, it correctly indicates pregnancy 96% of the time. A woman who is not pregnant gets a cor
D
The table below shows the results of a survey of 34 moviegoers given the statement, "There is too much violence in movies."
Opinion Rating: Frequency
Strongly Disagree: 2
Disagree: 7
No Opinion: 13
Agree: 5
Strongly Agree: 7
How much smaller is the propor
A
The XYZ Office Supplies Company sells calculators in bulk at wholesale prices, as well as individually at retail prices. Next year's sales depend on the market conditions, but executives use probability to find estimates of sales for the coming year. The
B
Suppose that the distribution of a set of scores has a mean of 47 and a standard deviation of 14. If 4 is added to each score, what will be the mean and the standard deviation (respectively) of the distribution of new scores?
A. 51 and 14
B. 51 and 18
C.
A
Suppose the probability of encountering an American who practices a particular religion is 0.014. What are the mean and standard deviation for the number of Americans in a random sample of 500 who practice this religion?
A. mean 0.014; standard deviation
E
Suppose that public opinion in a large city is 35% against increasing taxes to support the public school system. If a random sample of 500 people from this city are interviewed, what is the approximate probability that more than 200 of these people will n
D
The Correct Publishing Company claims that its publications will have errors only twice in every 100 pages. What is the approximate probability that Anne will read 235 pages of a 790 page book published by correct before finding an error?
A. 0.02%
B. 2%
C
...
A tetrahedral die has four sides numbered 1 through 4. Let X be a random variable that represents the sum of the numbers face up when two tetrahedral die are rolled.
(graph of probabilities associated with sum)
Sum: Probability
2: 1/16
3: 1/8
4: 3/16
5: 1
C
Reggie Richman has a poor driving record and must take out a special insurance policy. He wants to insure his $58,000 sports car. Based on previous driving records, AnyState has estimated the probability of various levels of loss per year as indicated in
A
Aldrich Ames is a convicted traitor who leaked American secrets to a foreign power. Yet Ames took routine lie detector tests and each time passed them. How can this be done? Recognizing control questions, employing unusual breathing patterns, biting one's
C
The heights of adult women are approximately normally distributed about a mean of 65 inches with a standard deviation of 2 inches. If Rachael is at the 99th percentile in height for adult women, then her height, in inches, is closest to
A. 60
B. 62
C. 68
D
At a college the scores on the Chemistry final exam are approximately normally distributed, with a mean of 75 and a standard deviation of 12. The scores on the calculus final are also approximately normally distributed, with a mean of 80 and a standard de
C
The admissions policy at a certain university requires that incoming students score in the upper 20% on a standardized test. If the mean score on the test is 510 and the standard deviation of the scores is 80, what its the minimum score that a student can
B
A recent study was conducted to investigate the duration of time required to complete a certain manual dexterity task. The reported mean was 10.2 seconds with a standard deviation of 16 seconds. Suppose the reported values are the true mean and standard d
B
A fair coin is flipped 10 times and the number of heads is counted. This procedure of 10 coin flips is repeated 100 times and the results are placed in a frequency table. Which of the frequency tables below is most likely to contain the results from these
C
Men's shirt sizes are determined by their neck sizes. Suppose that men's shirt sizes are approximately normally distributed with mean 15.7 inches and standard deviation 0.7 inch. A retailer sells men's shirts in sizes S, M, L, XL, where the shirt sizes ar
B