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Intro Stats, Books a la carte Plus NEW MyLab Statistics with Pearson eText -- Access Card Package (5th Edition)
5th Edition
ISBN: 9780134210247
Author: Richard D. De Veaux, Paul Velleman, David E. Bock
Publisher: PEARSON
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Textbook Question
Chapter 13, Problem 38E
Junk mail Direct mail advertisers send solicitations (a.k.a. “junk mail”) to thousands of potential customers in the hope that some will buy the company’s product. The acceptance rate is usually quite low. Suppose a company wants to test the response to a new flyer, and sends it to 1000 people randomly selected from their mailing list of over 200,000 people. They get orders from 123 of the recipients.
- a) Create a 90% confidence interval for the percentage of people the company contacts who may buy something.
- b) Explain what this interval means.
- c) Explain what “90% confidence” means.
- d) The company must decide whether to now do a mass mailing. The mailing won’t be cost-effective unless it produces at least a 5% return. What does your confidence interval suggest? Explain.
Expert Solution & Answer
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Question 2
The data below provides the battery life of thirty eight (38) motorcycle batteries.
100 83 83 105 110 81 114
99 101 105 78 115 74 96
106
89
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79 103 94 108 113 100
117 120
77 93
93 85 76
89 78 88
680
a. Test the hypothesis that mean battery life is greater than 90. Use the 1% level of
significance.
b. Determine if the mean battery life is different from 80. Use the 10% level of
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c. Would your conlcusion in part (b) change at the 5% level of significance? |
d. Confirm test results in part (b) using JASP. Note: All JASP input files and output
tables should be provided
Suppose that 80% of athletes at a certain college graduate. You randomly select eight athletes. What’s the chance that at most 7 of them graduate?
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Chapter 13 Solutions
Intro Stats, Books a la carte Plus NEW MyLab Statistics with Pearson eText -- Access Card Package (5th Edition)
Ch. 13.2 - You want to poll a random sample of 100 students...Ch. 13.2 - Prob. 2JCCh. 13.2 - If you think that about half the students are in...Ch. 13.3 - A Pew Research study regarding cell phones asked...Ch. 13.3 - Prob. 5JCCh. 13.3 - A Pew Research study regarding cell phones asked...Ch. 13.3 - Prob. 7JCCh. 13.3 - Prob. 8JCCh. 13.5 - Prob. 9JCCh. 13.5 - Prob. 10JC
Ch. 13.5 - Prob. 11JCCh. 13 - Website An investment company is planning to...Ch. 13 - Marketing The proportion of adult women in the...Ch. 13 - Prob. 3ECh. 13 - Character recognition An automatic character...Ch. 13 - Prob. 5ECh. 13 - Hows life? Gallup regularly conducts a poll using...Ch. 13 - Prob. 7ECh. 13 - Prob. 8ECh. 13 - Send more money The philanthropic organization in...Ch. 13 - Character recognition, again The automatic...Ch. 13 - Prob. 11ECh. 13 - Prob. 12ECh. 13 - Prob. 13ECh. 13 - Spanking In a 2015 Pew Research study on trends in...Ch. 13 - Prob. 15ECh. 13 - Smoking The Gallup poll described in Exercise 6...Ch. 13 - Prob. 17ECh. 13 - Prob. 18ECh. 13 - Graduation Its believed that as many as 25% of...Ch. 13 - Hiring In preparing a report on the economy, we...Ch. 13 - Margin of error A TV newscaster reports the...Ch. 13 - Another margin of error A medical researcher...Ch. 13 - Conditions For each situation described below,...Ch. 13 - More conditions Consider each situation described....Ch. 13 - Conclusions A catalog sales company promises to...Ch. 13 - More conclusions In January 2002, two students...Ch. 13 - Confidence intervals Several factors are involved...Ch. 13 - Confidence intervals, again Several factors are...Ch. 13 - Cars What fraction of cars made in Japan? The...Ch. 13 - Prob. 30ECh. 13 - Mislabeled seafood In 2013 the environmental group...Ch. 13 - Mislabeled seafood, second course A Consumer...Ch. 13 - Prob. 33ECh. 13 - Prob. 34ECh. 13 - Prob. 35ECh. 13 - Take the offer First USA, a major credit card...Ch. 13 - Teenage drivers An insurance company checks police...Ch. 13 - Junk mail Direct mail advertisers send...Ch. 13 - Prob. 39ECh. 13 - Prob. 40ECh. 13 - Prob. 41ECh. 13 - Gambling A city ballot includes a local initiative...Ch. 13 - Rickets Vitamin D, whether ingested as a dietary...Ch. 13 - Teachers A 2011 Gallup poll found that 76% of...Ch. 13 - Prob. 45ECh. 13 - Back to campus ACT, Inc. reported that 74% of 1644...Ch. 13 - Deer ticks Wildlife biologists inspect 153 deer...Ch. 13 - Prob. 48ECh. 13 - Graduation, again As in Exercise 19, we hope to...Ch. 13 - Better hiring info Editors of the business report...Ch. 13 - Prob. 51ECh. 13 - Another pilot study During routine screening, a...Ch. 13 - Prob. 53ECh. 13 - Amendment A TV news reporter says that a proposed...
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