Intro Stats
4th Edition
ISBN: 9780321826275
Author: Richard D. De Veaux
Publisher: PEARSON
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Chapter 16, Problem 13E
Conclusions A catalog sales company promises to deliver orders placed on the Internet within 3 days. Follow-up calls to a few randomly selected customers show that a 95% confidence interval for the proportion of all orders that arrive on time is 88% ± 6%. What does this mean? Are these conclusions correct? Explain.
- a) Between 82% and 94% of all orders arrive on time.
- b) Ninety-five percent of all random samples of customers will show that 88% of orders arrive on time.
- c) Ninety-five percent of all random samples of customers will show that 82% to 94% of orders arrive on time.
- d) We are 95% sure that between 82% and 94% of the orders placed by the sampled customers arrived on time.
- e) On 95% of the days, between 82% and 94% of the orders will arrive on time.
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West Virginia has one of the highest divorce rates in the nation, with an annual rate of approximately 5 divorces per 1000 people (Centers for Disease Control and Prevention website, January 12, 2012). The Marital Counseling Center, Inc. (MCC) thinks that the high divorce rate in the state may require them to hire additional staff.
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Excel File: data05-19.xls
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a. Is this probability distribution valid?
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f(x)
Σf(x)
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Select your answer
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Expected value
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For unemployed persons in the United States, the average number of months of unemployment at the end of December 2009 was approximately seven months (Bureau of Labor Statistics, January 2010). Suppose the following data are for a particular region in upstate New York. The values in the first column show the number of
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1029
2
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3487
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4652
7
4145
8
3587
9
2325
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2
3
4
5
6
7
8
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b. Show that your probability distribution satisfies the conditions for a valid discrete probability distribution.
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Chapter 16 Solutions
Intro Stats
Ch. 16.1 - A Pew Research study regarding cell phones asked...Ch. 16.1 - Prob. 2JCCh. 16.1 - A Pew Research study regarding cell phones asked...Ch. 16.1 - Prob. 4JCCh. 16.1 - Prob. 5JCCh. 16.2 - Prob. 6JCCh. 16.2 - Prob. 7JCCh. 16.2 - Prob. 8JCCh. 16 - Prob. 1ECh. 16 - Prob. 2E
Ch. 16 - Prob. 3ECh. 16 - Prob. 4ECh. 16 - Prob. 5ECh. 16 - 6. I asked, “How’s life?” In the Gallup poll...Ch. 16 - Prob. 7ECh. 16 - Prob. 8ECh. 16 - Margin of error A TV newscaster reports the...Ch. 16 - Another margin of error A medical researcher...Ch. 16 - Conditions For each situation described below,...Ch. 16 - More conditions Consider each situation described....Ch. 16 - Conclusions A catalog sales company promises to...Ch. 16 - More conclusions In January 2002, two students...Ch. 16 - Confidence intervals Several factors are involved...Ch. 16 - Confidence intervals, again Several factors are...Ch. 16 - Cars What fraction of cars made in Japan? The...Ch. 16 - Prob. 18ECh. 16 - Prob. 19ECh. 16 - Prob. 20ECh. 16 - Prob. 21ECh. 16 - Prob. 22ECh. 16 - 23. Contributions, please The Paralyzed Veterans...Ch. 16 - Take the offer First USA, a major credit card...Ch. 16 - Teenage drivers An insurance company checks police...Ch. 16 - Junk mail Direct mail advertisers send...Ch. 16 - Prob. 27ECh. 16 - Prob. 28ECh. 16 - Prob. 29ECh. 16 - Gambling A city ballot includes a local initiative...Ch. 16 - Rickets Vitamin D, whether ingested as a dietary...Ch. 16 - Teachers A 2011 Gallup poll found that 76% of...Ch. 16 - Prob. 33ECh. 16 - Back to campus ACT, Inc. reported that 74% of 1644...Ch. 16 - Deer ticks Wildlife biologists inspect 153 deer...Ch. 16 - Prob. 36ECh. 16 - Graduation Its believed that as many as 25% of...Ch. 16 - Hiring In preparing a report on the economy, we...Ch. 16 - Prob. 39ECh. 16 - Prob. 40ECh. 16 - Prob. 41ECh. 16 - Another pilot study During routine screening, a...Ch. 16 - Prob. 43ECh. 16 - Amendment A TV news reporter says that a proposed...
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