Statistics for Business & Economics, Revised (MindTap Course List)
12th Edition
ISBN: 9781285846323
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
Statistics for Business & Economics, Revised (MindTap Course List)
Ch. 8.1 - A simple random sample of 40 items resulted in a...Ch. 8.1 - 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 - A 95% confidence interval for a population mean...Ch. 8.1 - Data were collected on the amount spent by 64...Ch. 8.1 - Nielsen Media Research conducted a study of...Ch. 8.1 - The Wall Street Journal reported that automobile...Ch. 8.1 - Studies show that massage therapy has a variety of...Ch. 8.1 - AARP reported on a study conducted to learn how...Ch. 8.1 - Playbill magazine reported that the mean annual...
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 - Sales personnel for Skillings Distributors submit...Ch. 8.2 - A sample containing years to maturity and yield...Ch. 8.2 - The International Air Transport Association...Ch. 8.2 - Older people often have a hard time finding work....Ch. 8.2 - The average cost per night of a hotel room in New...Ch. 8.2 - Is your favorite TV program often interrupted by...Ch. 8.2 - Consumption of alcoholic beverages by young women...Ch. 8.2 - Disneys Hannah Montana: The Movie opened on Easter...Ch. 8.3 - How large a sample should be selected to provide a...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 - The U.S. Energy Information Administration (US...Ch. 8.3 - Annual starting salaries for college graduates...Ch. 8.3 - An online survey by ShareBuilder, a retirement...Ch. 8.3 - The travel-to-work time for residents of the 15...Ch. 8.3 - There has been a trend toward less driving in the...Ch. 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 - The Consumer Reports National Research Center...Ch. 8.4 - According to statistics reported on CNBC, a...Ch. 8.4 - Towers Perrin, a New York human resources...Ch. 8.4 - According to Thomson Financial, through January...Ch. 8.4 - Prob. 39ECh. 8.4 - For many years businesses have struggled with the...Ch. 8.4 - Fewer young people are driving. In 1983, 87% of...Ch. 8.4 - A poll for the presidential campaign sampled 491...Ch. 8.4 - A Phoenix Wealth Management/Harris Interactive...Ch. 8 - A sample survey of 54 discount brokers showed that...Ch. 8 - A survey conducted by the American Automobile...Ch. 8 - The 92 million Americans of age 50 and over...Ch. 8 - Many stock market observers say that when the P/E...Ch. 8 - US Airways conducted a number of studies that...Ch. 8 - A recent article reported that there are...Ch. 8 - Mileage tests are conducted for a particular model...Ch. 8 - In developing patient appointment schedules, a...Ch. 8 - Annual salary plus bonus data for chief executive...Ch. 8 - The National Center for Education Statistics...Ch. 8 - A USA Today/CNN/Gallup survey of 369 working...Ch. 8 - Which would be hardest for you to give up: Your...Ch. 8 - Prob. 56SECh. 8 - The 2003 Statistical Abstract of the United States...Ch. 8 - A well-known bank credit card firm wishes to...Ch. 8 - Workers in several industries were surveyed to...Ch. 8 - Although airline schedules and cost are important...Ch. 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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