Essentials Of Statistics For Business & Economics
9th Edition
ISBN: 9780357045435
Author: David R. Anderson, Dennis J. Sweeney, Thomas A. Williams, Jeffrey D. Camm, James J. Cochran
Publisher: South-Western College Pub
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Textbook Question
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 & Economics
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 - Cost of Dog Ownership. Money reports that the...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 - Gasoline Prices. The U.S. Energy Information...Ch. 8.3 - Salaries of Business Graduates. Annual starting...Ch. 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 - Health-Care Survey. In the spring of 2017, the...Ch. 8.4 - According to statistics reported on CNBC, a...Ch. 8.4 - Voter Sentiment. One of the questions Rasmussen...Ch. 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 - Driver’s License Rates. Fewer young people are...Ch. 8.4 - 42. A poll for the presidential campaign sampled...Ch. 8.4 - 43. The Pew Research Center Internet Project,...Ch. 8.5 - Federal Tax Return Errors. Suppose a sample of...Ch. 8.5 - Federal Government Employee Sick Hours. According...Ch. 8.5 - Web Browser Satisfaction. Internet users were...Ch. 8.5 - Speeding Drivers. In 2017, ABC News reported that...Ch. 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 - Healthy Sleep Duration. The Centers for Disease...Ch. 8 - The Health Care Cost Institute tracks health care...Ch. 8 - Obesity. Obesity is a risk factor for many health...Ch. 8 - Prob. 54SECh. 8 - 51. In developing patient appointment schedules, a...Ch. 8 - Prob. 56SECh. 8 - 53. The National Center for Education Statistics...Ch. 8 - A USA Today/CNN/Gallup survey of 369 working...Ch. 8 - Social Media Usage. The Pew Research Center has...Ch. 8 - Prob. 60SECh. 8 - The Centers for Disease Control reported the...Ch. 8 - A well-known bank credit card firm wishes to...Ch. 8 - Credit Card Ownership. Credit card ownership...Ch. 8 - 60. Although airline schedules and cost are...Ch. 8 - Driving Speeds. Huston Systems Private Limited...Ch. 8 - Prob. 66SECh. 8 - Prob. 67SECh. 8 - Prob. 68SECh. 8 - Young Professional Magazine Young Professional...Ch. 8 - Gulf Real Estate Properties Gulf Real Estate...Ch. 8 - Metropolitan Research, Inc.
Metropolitan Research,...
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