2017AP Statistics Free-Response Questions© 2017 The College Board. College Board, Advanced Placement Program, AP, AP Central, and the acorn logo are registered trademarks of the College Board. Visit the College Board on the Web: www.collegeboard.org. AP Central is the official online home for the AP Program: apcentral.collegeboard.org. www.mymathscloud.com
(II) Probability()()()()PA BPA PB PA Bª ©-4- ()()()PA BPABPB©()EXxpxiiÇμ22Var( )xixXxpis ÇμIf X has a binomial distribution with parameters n and p, then: ()(1)nknkPX kppkÈØÉÙÊÚnpxμ(1)nppxs ˆppμ(1)ˆpppnsIf x is the mean of a random sample of size nfrom an infinite population with mean μ and standard deviation , then: sxμμxnss2017 AP® STATISTICS FREE-RESPONSE QUESTIONS www.mymathscloud.com
-5- standard deviation of statisticstatistic parameterStandardized test statistic:Confidence interval: statistic critical valuestandard deviation of statisticSingle-Sample Statistic Sample Mean Standard Deviation of Statistic nsSample Proportion (1)ppnTwo-Sample Statistic Difference of sample means Standard Deviation of Statistic 211ns222nsSpecial case when 12ss1211nnsDifference of sample proportions 112 212(1)(1)ppp pnnSpecial case when 12pp1pp1211nn2observedexpectedChi-square test statisticexpectedÇ(III) Inferential Statistics 2017 AP® STATISTICS FREE-RESPONSE QUESTIONS www.mymathscloud.com
2017 AP® STATISTICS FREE-RESPONSE QUESTIONS © 2017 The College Board. Visit the College Board on the Web: www.collegeboard.org. GO ON TO THE NEXT PAGE. -6- STATISTICS SECTION II Part A Questions 1-5 Spend about 65 minutes on this part of the exam. Percent of Section II score — 75 Directions: Show all your work. Indicate clearly the methods you use, because you will be scored on the correctness of your methods as well as on the accuracy and completeness of your results and explanations. 1. Researchers studying a pack of gray wolves in North America collected data on the length x, in meters, fromnose to tip of tail, and the weight y, in kilograms, of the wolves. A scatterplot of weight versus length revealeda relationship between the two variables described as positive, linear, and strong.(a) For the situation described above, explain what is meant by each of the following words.(i) Positive: (ii) Linear: (iii) Strong: The data collected from the wolves were used to create the least-squares equation =- +ˆ16.4635.02 .yx(b) Interpret the meaning of the slope of the least-squares regression line in context. (c) One wolf in the pack with a length of 1.4 meters had a residual of 9.67- kilograms. What was the weight of the wolf? www.mymathscloud.com
