Question 2.5-2.10 Show work
530 CHAPTER 7 SAMPLING DISTRIBUTIONS digits = incorrect. Ten digits from the table simulate (a) 404 (b) 10 answers. (b) 411 (e) One digit from the random digit table simulates one (c) 418 answer, with odd = correct and even = incorrect. Ten digits from the table simulate 10 answers. (d) 425 (d) One digit from the random digit table simulates (e ) 448 one answer, with 0 or 1 = correct and all other AP2.8 You work for an advertising agency that is preparing (d) digits = incorrect, ignoring repeats. Ten digits from the a new television commercial to appeal to women table simulate 10 answers. You have been asked to design an experiment to (e) Two digits from the random digit table simulate compare the effectiveness of three versions of the one answer, with 00 to 20 = correct and 21 to commercial. Each subject will be show be shown one of the 99 = incorrect. Ten pairs of digits from the table three versions and then asked to reveal her attitude simulate 10 answers. toward the product. You think there may be large AP2.5 Suppose we roll a fair die four times. What is the differences in the responses of women who are employed and those who are not. Because of these probability that a 6 occurs on exactly one of the differences, you should use rolls? (a) a block design, but not a matched pairs design. (b) a completely randomized design. (c) a matched pairs design. (d) a simple random sample. (e) a stratified random sample. AP2.9 Suppose that you have torn a tendon and are facing surgery to repair it. The orthopedic surgeon explains the risks to you. Infection occurs in 3% of such oper ations, the repair fails in 14%, and both infection and failure occur together 1% of the time. What is the probability that the operation is successful for someone who has an operation that is free from AP2.6 On one episode of his show, a radio show host infection? encouraged his listeners to visit his website and vote (a) 0.8342 in a poll about proposed tax increases. Of the 4821 (b) 0.8400 people who vote, 4277 are against the proposed (c) 0.8600 increases. To which of the following populations should the results of this poll be generalized? (d) 0.8660 (a) All people who have ever listened to this show (e) 0.9900 (b) All people who listened to this episode of the show AP2.10 Social scientists are interested in the association (c) All people who visited the show host's website between high school graduation rate (HSGR, mea- (d) All people who voted in the poll sured as a percent) and the percent of U.S. fami- lies living in poverty (POV). Data were collected (e) All people who voted against the proposed increases from all 50 states and the District of Columbia, AP2.7 The number of unbroken charcoal briquets in a and a regression analysis was conducted. The 20-pound bag filled at the factory follows a Normal resulting least-squares regression line is given by distribution with a mean of 450 briquets and a stan- POV = 59.2 - 0.620( HSGR) with r = 0.802 dard deviation of 20 briquets. The company expects Based on the information, which of the following that a certain number of the bags will be underfilled, is the best interpretation for the slope of the least- so the company will replace for free the 5% of bags squares regression line? that have too few briquets. What is the minimum (a) For each 1% increase in the graduation rate, the number of unbroken briquets the bag would have to percent of families living in poverty is predicted to contain for the company to avoid having to replace decrease by approximately 0.896. the bag for free
