A school is having a contest in which students guess the number of candies in a jar. The student whose guess is closest to the correct number of candies in the jar wins a prize. The number of candies guessed by male and female students is shown in the back-to-back stemplot. Which of the following is true about the distribution of guesses?

The distributions of guesses for male and female students are both skewed to the left.

The distribution of guesses for male students is skewed to the left, and the distribution of guesses for female students is skewed to the right.

The distribution of guesses for male students is skewed to the right, and the distribution of guesses for female students is skewed to the left.

The distributions of guesses for male and female students are both skewed to the right.

The distributions of guesses for male and female students are both symmetric.

Which of the following statements must be true about the data sets A and B displayed in the histograms?

The standard deviation of data set A is greater than the standard deviation of data set B.

The mean of data set A is equal to the mean of data set B.

The median of data set A is equal to the median of data set B.

The range of data set A is equal to the range of data set B.

The standard deviation of data set A is less than the standard deviation of data set B.

A pollster is interested in comparing the proportions of women and men in a particular town who are in favor of a ban on fireworks within town borders. The pollster plans to test the hypothesis that the proportion of women in favor of the ban is different from the proportion of men in favor of the ban. There are 4,673 women and 4,502 men who live in the town. From a simple random sample of 40 women in the town, the pollster finds that 38 favor the ban. From an independent simple random sample of 50 men in the town, the pollster finds that 27 favor the ban. Which of the following statements is true about this situation?

A two-proportion z -test would not be valid for these data.

Because the samples are from normal populations, a two-proportion z -test would be valid.

Because the size of each sample is greater than 30, a two-proportion z -test would be valid.

Because the number who favored the ban is greater than 10 in both groups, a two-proportion z -test would be valid.

Because of the relative sizes of the populations and samples, a two-proportion z -test would be valid.

The p -value for a one-sided t -test is 0.10. If the test had been two-sided, what would the p -value have been?

It depends on the direction of the alternative hypothesis.

A scatterplot of student height, in inches, versus corresponding arm span length, in inches, is shown below. One of the points in the graph is labeled A . If the point labeled A is removed, which of the following statements would be true?

The slope of the least squares regression line increases and the correlation coefficient increases.

The slope of the least squares regression line is unchanged and the correlation coefficient increases.

The slope of the least squares regression line is unchanged and the correlation coefficient decreases.

The slope of the least squares regression line increases and the correlation coefficient decreases.

The slope of the least squares regression line decreases and the correlation coefficient increases.

A researcher constructed a 95 percent confidence interval for the mean number of alfalfa weevils on an alfalfa plant within a field. Based on 80 randomly selected alfalfa plants, the researcher found an average of 2.5 alfalfa weevils per plant and computed the 95 percent confidence interval to be 1.50 to 3.50. Which of the following statements is a correct interpretation of the 95 percent confidence level?

If we repeatedly sampled this field, taking samples of 80 plants and constructing 95% confidence intervals, then, approximately 95 percent of these intervals would include the population mean number of alfalfa weevils on an alfalfa plant in this field.

Approximately 95 percent of alfalfa fields sampled will have an average of 1.50 to 3.50 alfalfa weevils per plant, but nothing can be said about the sample mean number of alfalfa weevils for this or any other field.

Approximately 95 percent of alfalfa fields sampled will have an average of 1.50 to 3.50 alfalfa weevils per plant. The sample mean for this field was 2.50 alfalfa weevils per plant, but the sample means for other fields may be different.

If we repeatedly sampled this field, taking samples of 80 plants and constructing 95% confidence intervals, then, approximately 95 percent of these intervals would include 2.5, the mean for the sample described above.

If we repeatedly sampled this field, taking samples of 80 plants and constructing 95% confidence intervals, then, approximately 95 percent of these intervals would include the sample mean for that sample.

An amateur men’s swimming association is trying to decide whether times in the 100-meter breaststroke will be reduced if the men shave their heads. From the population of swimmers, six were selected at random and agreed to swim two races — one before shaving their heads and one after shaving their heads. The results for each race, with times in seconds, are given in the table. Let μ 1 represent the population mean of swimming times before shaving and μ 2 represent the population mean of swimming times after shaving. Let μ d represent the population mean of the differences, X 1 - X 2 . These differences follow a normal distribution. Which of the following would be the most appropriate test and alternative hypothesis to use in testing this theory?

A paired t -test with H a : μ d > 0

A two-sample t -test with H a : μ 1 > μ 2

A two-sample t -test with H a : μ 1 ≠ μ 2

A two-sample t -test with H a : μ 1 < μ 2

A paired t -test with H a : μ d ≠ 0

A newspaper poll found that 52 percent of the respondents in a large random sample of likely voters in a district intend to vote for candidate Smith rather than the opponent. A 95 percent confidence interval for the population proportion was computed to be 0.52 ± 0.04. Based on the confidence interval, which of the following should the newspaper report to its readers?

No prediction about who will win can be made with 95% confidence.

Smith will win because a majority of voters are in favor of Smith.

There is a 95% chance that Smith will win.

The poll predicts Smith will win, but there is a 5% chance that the prediction is incorrect due to sampling error.

With 95% confidence, there is convincing evidence that Smith will win.

A controversial issue in the sport of professional soccer is the use of instant replay for making difficult goal line decisions. Each person in a representative sample of 102 players, fans, coaches, and officials was asked his or her opinion about the use of instant replay for goal-line decisions. The data are summarized in the two-way frequency table. In testing to see whether opinion with respect to the use of instant replay is independent of the category of the person interviewed, a chi-square test statistic of 27.99 and a p -value less than 0.001 were calculated. Which of the following statements is correct?

The small p -value suggests that there is evidence of an association between category and opinion about the use of instant replay.

The number of degrees of freedom for the test is 8 - 1 = 7.

The chi-square test should not have been used because two of the counts in the table are less than 5.

The null hypothesis states that there is an association between category and opinion about the use of instant replay, and the small p -value suggests that the null hypothesis should be rejected.

The chi-square test shows that fans favor the use of instant replay.

A large clinical trial was designed to determine whether a certain vitamin improves the general health of adults. The investigators first identified 85 variables that measure various aspects of the general health of adults. Because each adult in the clinical trial was to serve as his or her own control, the 85 variables were measured for each adult, both before taking the vitamin and after taking the vitamin for three months. The investigators then performed 85 matched-pair t -tests, one for each variable. They found statistically significant results at the 0.05 level in 2 of the variables, both in the direction of improved general health. Which of the following should the investigators conclude?

There is insufficient evidence that the vitamin improves the health of adults because at the 0.05 significance level, one could easily get statistically significant results in 2 out of 85 tests just due to chance variability.

There is evidence that the vitamin improves the health of adults because 2 of the 85 tests were statistically significant.

There is evidence that the vitamin improves the health of adults because in clinical trials investigators typically underestimate the proportion of the population that is helped by a vitamin.

There is insufficient evidence that the vitamin improves the health of adults because the sample size of 85 is not large enough to draw a conclusion.

No conclusion can be drawn because an even number of variables is needed for a matched-pairs design.

Administrators at a state university computed the mean GPA (grade point average) for juniors and seniors majoring in either physics or chemistry. The results are displayed in the table below. When juniors and seniors are grouped together, could physics majors have a higher mean GPA than chemistry majors?

Yes. It could happen. Whether it does happen depends on the number of juniors and seniors in each major.

No. The physics majors’ mean GPA for juniors and seniors must be 3.0, while the chemistry majors’ mean GPA for juniors and seniors must be 3.3.

No. There is not enough information to determine the mean GPA for each major, but it must be higher for chemistry majors than for physics majors.

Yes. It could happen. Whether it does happen depends on the variability of the GPAs within each of the four groups of students.

Yes. It could happen. Whether it does happen depends on the shapes of the distributions of the GPAs for each of the four groups of students.

A department store manager wants to know if a greater proportion of customers on the store’s mailing list would redeem a coupon for $5 off the price of an item than would redeem a coupon for 10 percent off the price of an item. The manager mails a $5 off coupon to a random sample of 500 customers and mails a 10 percent off coupon to an independent random sample of 500 customers. The number of coupons of each type that were redeemed was recorded. Assuming that the conditions for inference are met, what test procedure should be used to answer the manager’s question?

A two-sample z -test for a difference between two proportions

A one-sample t -test for a mean

A one-sample z -test for a proportion

A t -test for the slope of a regression line

A matched-pairs t -test for a mean difference

A one-sided hypothesis test is to be performed with a significance level of 0.05. Suppose that the null hypothesis is false. If a significance level of 0.01 were to be used instead of a significance level of 0.05, which of the following would be true?

The probability of a Type II error would increase and the power of the test would decrease.

Neither the probability of a Type II error nor the power of the test would change.

Both the probability of a Type II error and the power of the test would decrease.

Both the probability of a Type II error and the power of the test would increase.

The probability of a Type II error would decrease and the power of the test would increase.

Which of the following distinguishes an observational study from a randomized experiment?

In an observational study treatments are not randomly assigned, whereas in a randomized experiment treatments are randomly assigned.

In an observational study volunteers are always used, whereas in a randomized experiment a random sample is always taken from the population.

In an observational study a random sample is always taken from the population, whereas in a randomized experiment volunteers are always used.

In an observational study a control group is never used, whereas in a randomized experiment a control group is always used.

An observational study can be double-blind, whereas a randomized experiment can only be single-blind because the experimenter determines who is randomly assigned to each treatment.

Frank, who lives in Texas, and his sister Lilly, who lives in Japan, correspond regularly. From what he can tell from the postmarks on both his and his sister’s letters, it appears that it takes longer for Lilly’s mail from Japan to reach him in Texas than it does for his letters from Texas to reach her in Japan. When Frank called his post office to ask if there was a reason for this, the postmaster told him that the delivery time of letters in both directions should be the same. Frank and his sister decided to collect data to see if letters from Japan to Texas take longer to be delivered than letters from Texas to Japan. They recorded the delivery time in days. After convincing themselves that the assumptions were reasonable, they performed a two-sample t -test and obtained the following computer output. Using a significance level of 0.05, which of the following statements best describes the conclusion that can be drawn from these data?

There is not convincing evidence that the mean delivery time from Japan to Texas is greater than the mean delivery time from Texas to Japan.

There is convincing evidence that there is no difference in the mean delivery times.

There is convincing evidence that there is a difference in the mean delivery times.

There is convincing evidence that the mean delivery time from Japan to Texas is greater than the mean delivery time from Texas to Japan.

The t -test cannot be used for sample sizes that are this small.

In a national study on transportation patterns, 1,000 randomly selected adults will be asked the question: How many trips per week do you make to the grocery store? The sample mean will be computed. Let μ denote the population mean response to the question if everyone in the population is to be asked the question. Is the sample mean x-bar unbiased for estimating μ ?

Yes, because for random samples the mean (expected value) of the sample mean x-bar is equal to the population mean μ.

Yes, because with a sample size of 1,000 the standard deviation of the sample mean x-bar is small.

Yes, because the wording of the question is not biased.

No, because the sample mean x-bar does not always equal the population mean μ.

No, because number of trips to the grocery store is not normally distributed so the mean (expected value) of the sample mean x-bar does not equal the population mean μ.

AP Statistics - 2014 Quiz

1.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

Heights, in inches, for the 200 graduating seniors from Washington High School are summarized in the frequency table. Which of the following statements about the median height is true?

It is greater than or equal to 78 inches.

It is greater than or equal to 72 inches but less than 78 inches.

It is greater than or equal to 66 inches but less than 72 inches.

It is greater than or equal to 60 inches but less than 66 inches.

It is less than 60 inches.

Tags

CCSS.HSS.ID.A.2

CCSS.HSS.ID.A.3

2.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

Professor James gave the same test to his three sections of statistics students. On the 35-question test, the highest score was 32 and the lowest was 15. Based on the information displayed in the boxplots above, which of the following statements is true?

Section 1 has the smallest interquartile range.

The lowest score in section 2 is higher than the highest score in either of the other sections.

Section 2 has the smallest range of scores.

The top 25% of scores in section 2 are lower than the highest score in section 3.

At least 50% of the scores in section 3 are higher than all of the scores in section 1.

Tags

CCSS.HSS.ID.A.1

CCSS.HSS.ID.A.2

CCSS.HSS.ID.A.3

3.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

A well-designed experiment should have which of the following characteristics?

I. Subjects assigned randomly to treatments

II. A control group or at least two treatment groups

III. Replication

I only

I and II only

I and III only

II and III only

I, II, and III

Tags

CCSS.HSS.IC.B.3

CCSS.HSS.IC.B.5

4.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

The distribution of colors of candies in a bag is as follows. If two candies are randomly drawn from the bag with replacement, what is the probability that they are the same color?

0.09

0.22

0.25

0.75

0.78

Tags

CCSS.HSS.CP.A.1

CCSS.HSS.CP.A.2

CCSS.HSS.CP.B.8

CCSS.HSS.CP.B.9

5.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

Each of 133 children in a sample was asked to choose a pencil. Three different colors were available: yellow, red, and blue. The number of 2-year olds and 3-year olds who selected each color is shown in the table above. In a test of independence of age and color, which of the following is used as the expected cell count for 2-year olds who select a yellow pencil?

14

Tags

CCSS.HSS.CP.A.1

CCSS.HSS.CP.A.2

CCSS.HSS.CP.A.3

CCSS.HSS.CP.A.4

6.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

Approximately 52 percent of all recent births were boys. In a simple random sample of 100 recent births, 49 were boys and 51 were girls. The most likely explanation for the difference between the observed results and the expected results in this case is

bias

variability due to sampling

nonsampling error

a sampling frame that is incomplete

confounding

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.ID.B.5

7.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

Each person in a random sample of adults was asked how many DVDs he or she owned. Summary statistics are given below. Which of the following statements is true?

Seventy-five percent of the adults in the sample own more than 95 DVDs.

Fifty percent of the adults in the sample own between 0 and 129.4 DVDs.

The distribution of the number of DVDs owned appears to be approximately symmetric.

The interquartile range of the number of DVDs owned is 65.

The distribution of the number of DVDs owned contains outliers on both the low side and the high side.

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.ID.A.2

CCSS.HSS.ID.A.3

8.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

For flights from a particular airport in January, there is a 30 percent chance of a flight being delayed because of icy weather. If a flight is delayed because of icy weather, there is a 10 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 5 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?

0.065

0.335

0.350

0.450

0.665

Tags

CCSS.HSS.CP.A.1

CCSS.HSS.CP.A.3

CCSS.HSS.CP.B.6

CCSS.HSS.CP.B.7

CCSS.HSS.CP.B.8

9.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

A survey was administered to parents of high school students in a certain state to see if the parents thought the students’ academic needs were being met. To select the sample, the parents were divided into two groups— one group of parents who live in cities with populations of more than 100,000 and the other group of parents who live in cities with populations less than or equal to 100,000. A random sample of 100 parents from each group was taken. Which of the following statements about the sample of 200 parents is true?

It is a convenience sample because the sample of parents was easily obtained.

It is a stratified random sample because parents were randomly selected from each group.

It is a random cluster sample because parents were randomly selected from each group.

It is a random cluster sample because groups of high schools were randomly selected.

It is a systematic sample because the parents were systematically divided into two groups.

Tags

CCSS.HSS.IC.B.3

10.

MULTIPLE CHOICE QUESTION

30 sec • 1 pt

A popular computer card game keeps track of the number of games played and the number of games won on that computer. The cards are shuffled before each game, so the outcome of the game is independent from one game to the next and is based on the skill of the player. Let X represent the number of games that have been won out of 100 games. Under which of the following situations would X be a binomial random variable?

All games were played by the same player, whose skill improved over the course of the 100 games.

A group of 5 players of different skill levels were each allowed to play 20 games in a row.

A group of players of different skill levels were each allowed to play until they had lost 3 games and this resulted in 100 games played.

Two players of equal skill level each played one game a day for 50 days and their skill level did not change from day to day.

Two players of different skill levels competed by allowing one player to continue until a game was lost, then the other player to continue until a game was lost, and so on, until 100 games were played.

Tags

CCSS.HSS.CP.A.2

AP Statistics - 2014

40 questions

Heights, in inches, for the 200 graduating seniors from Washington High School are summarized in the frequency table. Which of the following statements about the median height is true?

Professor James gave the same test to his three sections of statistics students. On the 35-question test, the highest score was 32 and the lowest was 15. Based on the information displayed in the boxplots above, which of the following statements is true?

A well-designed experiment should have which of the following characteristics?

I. Subjects assigned randomly to treatments

II. A control group or at least two treatment groups

III. Replication

The distribution of colors of candies in a bag is as follows. If two candies are randomly drawn from the bag with replacement, what is the probability that they are the same color?

Approximately 52 percent of all recent births were boys. In a simple random sample of 100 recent births, 49 were boys and 51 were girls. The most likely explanation for the difference between the observed results and the expected results in this case is

Each person in a random sample of adults was asked how many DVDs he or she owned. Summary statistics are given below. Which of the following statements is true?

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AP Statistics - 2014

40 questions

Heights, in inches, for the 200 graduating seniors from Washington High School are summarized in the frequency table. Which of the following statements about the median height is true?

Professor James gave the same test to his three sections of statistics students. On the 35-question test, the highest score was 32 and the lowest was 15. Based on the information displayed in the boxplots above, which of the following statements is true?

A well-designed experiment should have which of the following characteristics? I. Subjects assigned randomly to treatments II. A control group or at least two treatment groups III. Replication

The distribution of colors of candies in a bag is as follows. If two candies are randomly drawn from the bag with replacement, what is the probability that they are the same color?

Approximately 52 percent of all recent births were boys. In a simple random sample of 100 recent births, 49 were boys and 51 were girls. The most likely explanation for the difference between the observed results and the expected results in this case is

Each person in a random sample of adults was asked how many DVDs he or she owned. Summary statistics are given below. Which of the following statements is true?

Create a free account and access millions of resources

Similar Resources on Wayground

Popular Resources on Wayground

Discover more resources for Mathematics

A well-designed experiment should have which of the following characteristics?

I. Subjects assigned randomly to treatments

II. A control group or at least two treatment groups

III. Replication