AP Statistics Name That Test

A random sample of 100 people from Country S had 15 people with blue eyes. A separate random sample of 100 people from Country B had 25 people with blue eyes. Assuming all conditions are met, which of the following is a 95 percent confidence interval to estimate the difference in population proportions of people with blue eyes (Country S minus Country B) ?

• (-0.01, 0.21)

• (-0.15,-0.05)

• (-0.19,-0.01)

• (-0.21, 0.01)

• (-0.24,0.04)

A study reports that 75 percent of young adults in a county get their news from online sources. A sociologist believes that the percentage is actually greater than 75 percent. The sociologist will select a random sample of young adults from around the county to interview. Which of the following is the most appropriate method for investigating the sociologist’s belief?

• A one-sample -test for a difference in population proportions

• A one-sample -test for a sample proportion

• A one-sample -test for a population proportion

• A two-sample -test for a difference in population proportions

• A two-sample -test for a difference in sample proportions

A report on a certain fast food restaurant states that , the mean order total, is $9. The manager of the restaurant believes the mean is higher. A random sample of orders will be selected. The sample mean will be calculated and used in a hypothesis test to investigate the belief. Which of the following is the correct set of hypotheses?

A company that manufactures laptop batteries claims the mean battery life is 16 hours. Assuming the distribution of battery life is approximately normal, a consumer group will conduct a hypothesis test to investigate whether the battery life is less than 16 hours. The group selected a random sample of 14 of the batteries and found an average life of 15.6 hours with a standard deviation of 0.8 hour. Which of the following is the correct test statistic for the hypothesis test?

A company director investigated whether there is a difference in the mean number of overtime hours worked each week by employees assigned to two different managers. Each manager, A and B, manages 100 employees. Random samples of 35 employees from manager A and 40 employees from manager B were selected. The number of overtime hours worked was recorded for the 75 employees each week. Have the conditions been met for inference with a confidence interval for the difference in the population means?

• Yes, all conditions have been met.

• No, because the data were not collected using a random method.

• No, because the size of at least one of the samples is greater than 10 percent of the population.

• No, because the sample sizes are not large enough to assume the distribution of the difference in sample

  means is normal.

• No, because the sample sizes are not the same.

The campus bookstore at a local university is interested in finding out whether the textbook preference and the class level (freshman, sophomore, junior, senior) of the student are associated. A random sample of 100 students is obtained, and each student in the sample is asked which textbook he or she prefers: new books, used books, or digital books. The students are also asked whether their class level is freshman, sophomore, junior, or senior. Which of the following is the appropriate test for the investigation?

• A one-sample -test for a population mean

• A two-sample -test for a difference between mea

• A chi-square goodness-of-fit test

• A chi-square test of homogeneity

• A chi-square test of independence

A state political analyst wanted to see whether there is an association between the region where a person lives and whether the person is in favor of increasing the state gas tax. A random sample of 270 state residents was selected, and the table below shows the results of the survey. Which of the following is closest to the -value of the appropriate test to investigate whether there is an association between the region where a person lives and whether the person is in favor of increasing the state gas tax, and what is the correct decision?

• 0.0644, we reject the null hypothesis

• 0.3596, we reject the null hypothesis

• 0.0644, we fail to reject the null hypothesis

• 0.3596, we fail to reject the null hypothesis

To compare 2 dog-training programs, an obedience school trained 43 dogs using Program A and 41 dogs using Program B. For Program A, the average number of training hours required was 24.8 with a standard deviation of 3.1 hours. For Program B, the mean was 22.9 hours with a standard deviation of 3.3 hours. Is there a significant difference between the two programs?

• One-Sample Z Test for a Proportion

• One-Sample Z Test for a Mean

• Two-Sample T Test for the Difference in Means

• Two-Sample Z Test for the Difference in Means

In 1975, a random sample of 1484 adult U.S. citizens was surveyed, and 193 strongly agreed with the statement, "People should take care of themselves". Then, in 1991, a survey of 1013 adult U.S. citizens showed that only 61 strongly agreed with the statement. Does this indicate that the proportion of U.S.adults who strongly agree with the given statement has dropped?

• Two-Sample Z Test for the Difference in Proportions

• Two-Sample T Test for the Difference in Means

• Matched Pairs T Test for a Mean

• One-Sample T Test for a Mean

Which test would you use to see if the distribution of music that Californians listen to is the same as that of Nevadans?  900 Californians and 600 Nevadans were surveyed.

• Chi-square Goodness of Fit Test

• Chi-Square Test for Homogeneity

• Chi-Square Test for Independence/Association

• Not a Chi-square test