APStatisticsMultipleChoiceExam统计选择题.docx

1、APStatisticsMultipleChoiceExam统计选择题2007-AP-Statistics-Multiple-Choice-Exam统计选择题D4. Independent random samples of 100 luxury cars and 250 non-luxury cars in a certain city are examined to see if they have bumper stickers. Of the 250 non-luxury cars, 125 have bumper stickers and of the 100 luxury cars

2、, 30 have bumper stickers. Which of the following is a 90 percent confidence interval for the difference in the proportion of non-luxury cars with bumper stickers and the proportion of luxury cars with bumper stickers from the population of cars represented by these samples?(A) (B) (C) (D) (E) 5. A

3、safety group claims that the mean speed of drivers on a highway exceeds the posted speed limit of 65 miles per hour (mph). To investigate the safety groups claim, which of the following statements is appropriate?(A) The null hypothesis is that the mean speed of drivers on this highway is less than 6

4、5 mph.(B) The null hypothesis is that the mean speed of drivers on this highway is greater than 65 mph.(C) The alternative hypothesis is that the mean speed of drivers on this highway is greater than 65 mph.(D) The alternative hypothesis is that the mean speed of drivers on this highway is less than

5、 65 mph.(E) The alternative hypothesis is that the mean speed of drivers on this highway is greater than or equal to 65 mph.6. A fair coin is to be flipped 5 times. The first 4 flips land heads up. What is the probability of heads on the next (5th) flip of this coin?(A) (B) (C) (D) (E) 7. The stempl

6、ot below shows the yearly earnings per share of stock for two different companies over a sixteen-year period. Company A Company B 0 58, 75, 96, 98 92, 91, 90, 82, 78, 43, 38, 26 1 01, 10, 17, 21, 43, 43, 53, 65, 73 49, 47, 44, 00 2 09, 27, 29 73, 27, 05, 02 3 Which of the following statements is tru

7、e?(A) The median of the earnings of Company A is less than the median of the earnings of the Company B.(B) The range of the earnings of Company A is less than the range of the earnings of Company B.(C) The third quartile of Company A is smaller than the third quartile of Company B.(D) The mean of th

8、e earnings of Company A is greater than the mean of the earnings of Company B.(E) The interquartile range of Company A is twice the interquartile range of Company B.8. Let X represent a random variable whose distribution is normal, with a mean of 100 and a standard deviation of 10. Which of the foll

9、owing is equivalent to P(X 115)?(A) P(X 115)(B) P(X 115)(C) P(X 85)(D) P(85 X 115)(E) 1 - P(X 85)9. A television news editor would like to know how local registered voters would respond to the question, Are you in favor of the school bond measure that will be voted on in an upcoming special election

10、? A television survey is conducted during a break in the evening news by listing two telephone numbers side by side on the screen, one for viewers to call if they approve of the bond measure, and the other to call if they disapprove. This survey method could produce biased results for a number of re

11、asons. Which one of the following is the most obvious reason?(A) It uses a stratified sample rather than a simple random sample. (B) People who feel strongly about the issue are more likely to respond. (C) Viewers should be told about the issues before the survey is conducted.(D) Some registered vot

12、ers who call might not vote in the election.(E) The wording of the question is biased.10. A high school physics teacher was conducting an experiment with his class on the length of time it will take a marble to roll down a sloped chute. The class ran repeated trials in order to determine the relatio

13、nship between the length, in centimeters, of the sloped chute and the time, in seconds, for the marble to roll down the chute. A linear relationship was observed and the correlation coefficient was 0.964. After discussing their results, the teacher instructed the students to convert all of the lengt

14、h measurements to meters but leave the time in seconds. What effect will this have on the correlation of the two variables?(A) Because the standard deviation of the lengths in meters will be one hundredth of the standard deviation of the lengths in centimeters, the correlation will decrease by one h

15、undredth to 0.954.(B) Because the standard deviation of the lengths in meters will be one hundredth of the standard deviation of the lengths in centimeters, the correlation will decrease proportionally to 0.00964.(C) Because changing from centimeters to meters does not affect the value of the correl

16、ation, the correlation will remain 0.964.(D) Because only the length measurements have been changed, the correlation will decrease substantially.(E) Because meters are a much more common measurement for length in determining speed, the linear relationship of the data will be stronger and thus the co

17、rrelation will increase substantially.11. Julie generates a sample of 20 random integers between 0 and 9 inclusive. She records the number of 6s in the sample. She repeats this process 99 more times, recording the number of 6s in each sample. What kind of distribution has she simulated?(A) The sampl

18、ing distribution of the sample proportion with n = 20 and p = 0.6(B) The sampling distribution of the sample proportion with n = 100 and p = 0.1(C) The binomial distribution with n = 20 and p = 0.1(D) The binomial distribution with n = 100 and p = 0.1(E) The binomial distribution with n = 20 and p =

19、 0.6nMeanMedianSample I2142.645.0Sample II2649.248.512. The table above 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?(A) (B) (C) (D) (E) It cannot be determined from the information given.13. Dan, a tra

20、iner at the Popular Gym, was interested in comparing levels of physical fitness of students attending a nearby community college and those attending a 4-year college in town. He selected a random sample of 320 students from the community college. The mean and standard deviation of their fitness scor

21、es were 95 and 10, respectively. Dan also selected a random sample of 320 students from a 4-year college. The mean and standard deviation of their fitness scores were 92 and 13, respectively. He then conducted a two-sided t-test that resulted in a t-value of 3.27. Which of the following is an approp

22、riate conclusion from this study?(A) Because the sample means only differed by 3, the population means are not significantly different.(B) Because the second group had a larger standard deviation, their mean fitness score is significantly higher.(C) Because the second group had a larger standard dev

23、iation, the mean fitness score of the first group is significantly higher.(D) Because the p-value is less than = 0.05, the mean fitness scores for the two groups of students are significantly different.(E) Because the p-value is greater than = 0.05, the mean fitness scores for the two groups of stud

24、ents are significantly different.14. 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 assigns th

25、e rest to the treatment. The major reason for separate assignment for men and women is that(A) it is a large study with 100 subjects(B) the new drug may affect men and women differently(C) the new drug may affect hypertensive and nonhypertensive people differently(D) this design uses matched pairs t

26、o detect the new-drug effect(E) there must be an equal number of subjects in both the placebo group and the treatment group.15. The histograms below represent the distribution of five different data sets, each containing 28 integers, from 1 through 7, inclusive. The horizontal and vertical scales ar

27、e the same for all graphs. Which graph represents the data set with the largest standard deviation.(A) (B) (C) (D) (E)16. Lynn is planning to fly from New York to Los Angeles and will take the Airtight Airlines flight that leaves at 8 A.M. The Web site she used to make her reservation states that th

28、e probability that the flight will arrive in Los Angeles on time is 0.70. Of the following, which is the most reasonable explanation for how that probability could have been estimated?(A) By using an extended weather forecast for the date of her flight, which showed a 30% chance of bad weather(B) By

29、 making assumptions about how airplanes work, and factoring all of those assumptions into an equation to arrive at the probability(C) From the fact that, of all airline flights arriving in California, 70% arrive on time(D) From the fact that, of all airline flights in the United States, 70% arrive o

30、n time(E) From the fact that, on all previous days this particular flight had been scheduled, it had arrived on time 70% of those days17. In an experiment, two different species of flowers were crossbred. The resulting flowers from this crossbreeding experiment were classified, by color of flower an

31、d stigma, into one of four groups, as shown in the table below.Flower Type Resulting from CrossbreedingNumber of Flowers Observed with These ColorsI: Magenta lower with green stigma115II: Magenta flower with red stigma49III: Red flower with green stigma32IV: Red flower with red stigma21A biologist e

32、xpected that the ratio of 9:3:3:1 for the flower types I:II:III:IV, respectively, would result from this crossbreeding experiment. From the data above, a value of approximately 8.04 was computed. Are the observed results inconsistent with the expected ratio at the 5 percent level of significance?(A) Yes, because the computed value is great