AP Statistics Chapter 4 Test questions and answers 2023/2024 verified to pass

AP Statistics Chapter 4 TestA school principal wanted to investigate student opinion about the food served in the school cafeteria. The principle selected at random samples of 50 first-year students, 50 second-year students, 50 third-year students, and 50 fourth-year students to complete a questionnaire. Which of the following best describes the principal's sampling plans. - correct answer (A) Stratified random sample An experiment will be conducted to determine whether children lean their multiplication facts better by practicing with flashcards or by practicing on a computer. Children who volunteer for the experiment will be randomly assigned to one of the 2 treatments. Because the children's gender may affect the outcome, there will be blocking by gender. After practice, the children will be given a test on their multiplication facts. Why will it be impossible to conduct a double-blind experiment. - correct answer (C) The child will know whether he or she used flash cards or the computer A regional transportation authority is interested in estimating the mean number of minutes working in the region spend commuting to work on a typical day. A random sample of working adults will be selected from each of of the 3 strata: urban, suburban, and rural. Selected individuals will be asked the number of minutes they spend commuting to work on a typical day. Why is stratification used in this situation? - correct answer (E) To decrease the variability in estimates of the mean commuting time A randomized block design will be used in an experiment to compare 2 lotions that protect people from getting sunburned. Which of the following would guide the formation of the blocks? - correct answer (D) Participants within each block should be as similar as possible with respect to how easily they get sunburned A well-designed experiment should have which of the following characteristics? I. Subjects assigned randomly to treatments II. A control group or at least 2 treatment groups III. Replication - correct answer (E) I, II, and III Approximately 52% of all recent births were boys. In a SRS 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. - correct answer (B) Variability due to sampling 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 2 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 00 parents from each group was taken. Which of the following statements about the sample of 200 parents is true? - correct answer (B) It is a stratified random sample because parents were randomly selected from each group In a recent poll of 1,500 randomly selected eligible voters, only 525 (35%) said that they did not vote in the last election. However, a vote count showed that 80% of eligible voters actually did not vote in the last election. Which of the following types of bias is most likely to have occurred in the poll? - correct answer (A) Non-response bias and (D) Response bias Which of the following distinguishes an observational study from a randomized experiment? - correct answer (C) In an observational study treatments are not randomly assigned, whereas in a randomized experiment treatments are randomly assigned A researcher conducting a telephone survey is concerned about possible sources of bias. Of the following, which is the best example of non-response bias? - correct answer (D) Many of the people selected to the survey who do not respond might have opinions different from those who do not respond At a large conference of teachers from a variety of subjects, a random sample of 50 mathematics teachers attending the conference was selected. Among the selected mathematics teachers, 28% had taken 1 or more courses in statistics. For which of the following populations is 28% a reasonable estimate of the percentage of those who have taken 1 or more courses in statistics? - correct answer (B) All mathematic teachers who attended the conference In a certain school, students can choose whether to eat in the school's cafeteria. A reporter working for the school's newspaper polled students on their reactions to changes in the menu at the cafeteria in 1 30-minute time period, the reporter used a coin to determine whether to stop the student and ask how he or she felt about the new menu. In the reporter's article it was stated that a random sample of the students showed that 89% of the school's student population was happy with the new menu. Which of the following statements is true? - correct answer (B) Because students self-selected whether to eat in the cafeteria, the sampling method might be biased and the sample might not be representative of all students in the school