# Ap Statistics Chapter 9 Homework

**Unformatted text preview: **AP STATISTICS ~— CHAPTER 9 PRACTICE TEST , ,LL and 0‘. are statistics. ' Wt“ x x l. True 0 Fals . rmmh ._ . 0 False: The standard deviation of the distribution of x decreases as n increases. [‘J 3. True The sampling distribution ofp tends to be more spread out for larger sample sizes than for smaller sample sizes. 4®r False: As H grows larger, the mean of the sampling distribution of x gets closer to ,u . MULTIPLE CHOICE 5. A statistic is said to be unbiased if a) The survey used to obtain the statistic was designed so as to avoid even the hint of racial or , sexual prejudice. The mean of its sampling distribution is equal to the true value of the parameter being estimated. Both the person who calculated the statistic and the subjects whose responses makeup the statistic were truthful. d) It is used for honest purposes only. e) None ofthe above. 6. Given that 58% of all gold dealers believe next year will be a good one to speculate in South African gold coins, in an SRS of 150 dealers, what is the approximate probability that between 55% and 60% believe that it will be a good year to speculate? .. .. ~ W .7 . age 31ng :: swig 5W “E‘s 4'“ a) 0.500 b) 01 192 g,» 7.... W7, M» ,7... .. . 0.3099 (fwél‘im 0.4619 s . 7. . 6) 09215 W... 7 5f W . éﬁiﬁ” .100} W mews 77., £9.50 W %m 7. Which of the following statements is (are) true? W ﬁ' 1. The sampling distribution of IC has standard deviation {7: even ifthc population is not H normally distributed. II. The sampling distribution of x is normal ifthe population has a normal distribution. III. When n is large, the sampling distribution a is approximately normal even if the population is not normally distributed. a) land 11 b) landlll II and HI 1, ll and III None of the above. 8. In a study of the effects of acid rain, a random sample of 100 trees from a particular forest is examined. 40% of these show some signs of damage. Which of the following statements is correct? 40% is a parameter. 40% is a statistic. 40% of all trees in the forest show some signs of damage. d) More than 40% of the trees in the forest show some signs of damage. e) Less than 40% of the trees in the forest show some signs of damage. 9. Referring to the previous problem, which of the following statements is correct? if} The sampling distribution of the proportion of damaged trees is approximately normal. b) If we took another random sample of trees, we would ﬁnd that 40% of these would show some signs of damage. c) If a sample of 1000 trees was examined, the variability of the sample proportion would be larger than in a sample of 100 trees. d) This is a comparative experiment. e) None of the above. FREE RESPONSE 10. Women’s heights are normally distributed with a mean 64.5 inches and standard deviation 2.5 inches. What is the probability that a randomly selected young woman is taller than 66.5 inches? What is the probability that the mean height of an SRS of 10 young women is greater than 66.5 inches? at. ﬁt‘f’nw . Suppose that you and your lab partner ﬂip a coin 20 times and you calculate the proportion of tails to be 0.7. Your partner seems surprised at these results and suspects that the coin is not fair. Write a brief statement that describes why you either agree or disagree with him. in. . a; 12. An opinion poll asks a random sample of 500 adults whether they favor giving parents of school-age children vouchers that can be exchanged for education at any private school of their choice. Each school would be paid by the government on the basis of how many vouchers it collected. Suppose that in fact 45% of the population favor this idea. /\ a. What is the mean ofthe sampling distribution of p , the proportion of adults in samples of 500 who favor giving parents of school —age children these vouchers? M. n .... if} “i f b. What 13 them stnrv1at1nof p ? 0% a... t} {33.2% . ‘ 1a c. Explam why you can 3% the formula for the standard deviation of p in this setting. {run at: was at i: marital mar at; saints a re { arias d. Check that vou can use the nonnal approximation for the distribution of p. er tar... M W31 it} {saw aware) are nit—w tiara Mari MW e. What is the probability that more than half of the sample is in favor? Do you have any reason to doubt the validity ofthe claim? (tlgiit: as} WWW“ wwmmwwwm a} W’ :> éé gm 5“} %W égé Smm g WWW§W§:WW M 3. w ﬁw @M w» M $322 NE x mm mm M fsiégfeﬁﬁmw’ m: mmw Em. mmwwm mm W 5% Wmmgﬂfﬁ Wm MWE Mﬁm WW §W€§ mm} mm wwm Wm, WM am; ‘ MM FM Wwam ngmgmw W ééwwéﬁ 3% WM Maﬁa} §§f mm @W wwwm Wémm m WW W. Swag M mm {*Wﬁaﬁmﬁ W w ﬁgmwm? wﬂmmﬁgg gm MM wwﬁaggsmg, ...

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AP Statistics- Chapter 9 Sampling Distributions The chapter 9 assignments will all be due on the day of your chapter 9 test. The chapter 9 test is scheduled on Monday, January 28 th for A-Day, Tuesday, January 29 th for B-Day, and on both of those days for 7 th period classes. You are still expected to keep up with the assignments throughout the chapter as the material builds and to be prepared for quizzes, as well as the test. All assignment packets MUST be turned in by the day of your scheduled test, absolutely NO exceptions ! You are more than welcome to turn in the assignment packet early, and you should make arrangements to have it turned in on time if you are going to be out on the day of your test. Your AP Statistics Teacher A general outline of Chapter 9: Dates Lesson Assignments Wednesday/Thursd ay Jan 16 th /17 th Chapter 9 Vocabulary Quiz 9.1-9.3: Sampling Distributions YMS Chapter 9 Questions Textbook #s: 9.1-9.4, 9.8, 9.10-9.13, 9.15, 9.17 Tuesday/Wednesda y Jan 22 nd /23 rd 9.1-9.3 Practice Problems AP Stat Ch 9 Problems Textbook #s: 9.19-9.29, 9.31-9.42 Thursday/Friday Jan 24 th /25 th Ch 9 Free Response Questions 9.1-9.3 Quiz Textbook #s: 9.43, 9.45-9.53 Monday/Tuesday Jan 28 th /29 th Chapter 9 Test *turn in Chapter 9 Assignments **Chapter 10 Reading Guide Please sign and return to your teacher. I understand that the chapter 9 assignment packet is due the day of my scheduled chapter 9 test (January 28 th /29 th ). I also understand that there will not be any allowance for late work. Name__________________________________________________ Signature_____________________________________ Date______________________

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