Essentials of Statistics for Business and Economics (with XLSTAT Printed Access Card)
8th Edition
ISBN: 9781337114172
Author: David R. Anderson, Dennis J. Sweeney, Thomas A. Williams, Jeffrey D. Camm, James J. Cochran
Publisher: Cengage Learning
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Chapter 8.4, Problem 42E
A poll for the presidential campaign sampled 491 potential voters in June. A primary purpose of the poll was to obtain an estimate of the proportion of potential voters who favored each candidate. Assume a planning value of p* = .50 and a 95% confidence level.
- a. For p* = .50, what was the planned margin of error for the June poll?
- b. Closer to the November election, better precision and smaller margins of error are desired. Assume the following margins of error are requested for surveys to be conducted during the presidential campaign. Compute the recommended
sample size for each survey.
| Survey | Margin of Error |
| September | .04 |
| October | .03 |
| Early November | .02 |
| Pre-Election Day | .01 |
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Chapter 8 Solutions
Essentials of Statistics for Business and Economics (with XLSTAT Printed Access Card)
Ch. 8.1 - A simple random sample of 40 items resulted in a...Ch. 8.1 - 2. A simple random sample of 50 items from a...Ch. 8.1 - A simple random sample of 60 items resulted in a...Ch. 8.1 - 4. A 95% confidence interval for a population mean...Ch. 8.1 - Data were collected on the amount spent by 64...Ch. 8.1 - Travel Taxes. In an attempt to assess total daily...Ch. 8.1 - 7. The average annual cost of the first year of...Ch. 8.1 - Studies show that massage therapy has a variety of...Ch. 8.1 - Cost to Repair Fire Damage. The mean cost to...Ch. 8.1 - 10. Costs are rising for all kinds of medical...
Ch. 8.2 - For a t distribution with 16 degrees of freedom,...Ch. 8.2 - Find the t value(s) for each of the following...Ch. 8.2 - The following sample data are from a normal...Ch. 8.2 - A simple random sample with n = 54 provided a...Ch. 8.2 - 15. Sales personnel for Skillings Distributors...Ch. 8.2 - Years to Bond Maturity. A sample containing years...Ch. 8.2 - Quality Ratings of Airports. The International Air...Ch. 8.2 - Unemployment in Older Workers. Older people often...Ch. 8.2 - Meal Cost in Hong Kong. The mean cost of a meal...Ch. 8.2 - Automobile Insurance Premiums. The average annual...Ch. 8.2 - Telemedicine. Health insurers are beginning to...Ch. 8.2 - Movie Ticket Sales. Marvel Studios motion picture...Ch. 8.3 - 23. How large a sample should be selected to...Ch. 8.3 - The range for a set of data is estimated to be 36....Ch. 8.3 - Refer to the Scheer Industries example in Section...Ch. 8.3 - Prob. 26ECh. 8.3 - Prob. 27ECh. 8.3 - 28. Many medical professionals believe that eating...Ch. 8.3 - 29. Customers arrive at a movie theater at the...Ch. 8.3 - Prob. 30ECh. 8.4 - A simple random sample of 400 individuals provides...Ch. 8.4 - A simple random sample of 800 elements generates a...Ch. 8.4 - In a survey, the planning value for the population...Ch. 8.4 - At 95% confidence, how large a sample should be...Ch. 8.4 - Prob. 35ECh. 8.4 - According to statistics reported on CNBC, a...Ch. 8.4 - Prob. 37ECh. 8.4 - 38. According to Franchise business review, over...Ch. 8.4 - In 16% of all homes with a stay-at-home parent,...Ch. 8.4 - Prob. 40ECh. 8.4 - Prob. 41ECh. 8.4 - 42. A poll for the presidential campaign sampled...Ch. 8.4 - Prob. 43ECh. 8 - 44. A sample survey of 54 discount brokers showed...Ch. 8 - 45. A survey conducted by the American Automobile...Ch. 8 - 46. The 92 million Americans of age 50 and over...Ch. 8 - Prob. 47SECh. 8 - The Health Care Cost Institute tracks health care...Ch. 8 - Prob. 49SECh. 8 - Prob. 50SECh. 8 - 51. In developing patient appointment schedules, a...Ch. 8 - Prob. 52SECh. 8 - 53. The National Center for Education Statistics...Ch. 8 - A USA Today/CNN/Gallup survey of 369 working...Ch. 8 - Prob. 55SECh. 8 - Prob. 56SECh. 8 - The Centers for Disease Control reported the...Ch. 8 - A well-known bank credit card firm wishes to...Ch. 8 - Prob. 59SECh. 8 - 60. Although airline schedules and cost are...Ch. 8 - Young Professional Magazine Young Professional...Ch. 8 - Gulf Real Estate Properties Gulf Real Estate...Ch. 8 - Metropolitan Research, Inc.
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