Statistics for Business & Economics
16th Edition
ISBN: 9781337325448
Author: Anderson
Publisher: CENGAGE C
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Textbook Question
Chapter 8.3, Problem 25E
Refer to the Scheer Industries example in Section 8.2. Use 6.84 days as a planning value for the population standard deviation.
- a. Assuming 95% confidence, what
sample size would be required to obtain a margin of error of 1.5 days? - b. If the precision statement was made with 90% confidence, what sample size would be required to obtain a margin of error of 2 days?
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PART 1 Getting Off to a Statistically Significant S
Chapter 8 Solutions
Statistics for Business & Economics
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 - In an attempt to assess total daily travel taxes...Ch. 8.1 - The average annual cost of the first year of...Ch. 8.1 - Studies show that massage therapy has a variety of...Ch. 8.1 - The mean cost to repair the smoke and fire damage...Ch. 8.1 - Costs are rising for all kinds of medical care....
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 mean cost of a meal for two in a mid-range...Ch. 8.2 - The average annual premium for automobile...Ch. 8.2 - Health insurers are beginning to offer...Ch. 8.2 - Marvel Studios motion picture Guardians of the...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 - Many medical professionals believe that eating too...Ch. 8.3 - Customers arrive at a movie theater at the...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 - One of the questions on a survey of 1000 adults...Ch. 8.4 - According to Franchise business review, over 50%...Ch. 8.4 - In 16% of all homes with a stay-at-home parent,...Ch. 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 - The Pew Research Center Internet Project,...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 - Russia has recently started a push for stronger...Ch. 8 - The Health Care Cost Institute tracks health care...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 - The Pew Research Center has conducted extensive...Ch. 8 - A survey of 750 likely voters in Ohio was...Ch. 8 - The Centers for Disease Control reported the...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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