Modern Business Statistics with Microsoft Excel (MindTap Course List)
5th Edition
ISBN: 9781285433301
Author: David R. Anderson, Dennis J. Sweeney, Thomas A. Williams
Publisher: Cengage Learning
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Textbook Question
Chapter 8.4, Problem 38E
According to Thomson Financial, through last month, the majority of companies reporting profits had beaten estimates. A sample of 162 companies showed that 104 beat estimates, 29 matched estimates, and 29 fell short.
- a. What is the point estimate of the proportion that fell short of estimates?
- b. Determine the margin of error and provide a 95% confidence interval for the proportion that beat estimates.
- c. How large a sample is needed if the desired margin of error is .05?
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Chapter 8 Solutions
Modern Business Statistics with Microsoft Excel (MindTap Course List)
Ch. 8.1 - 1. A simple random sample of 40 items resulted in...Ch. 8.1 - 2. A simple random sample of 50 items from a...Ch. 8.1 - 3. A simple random sample of 60 items resulted in...Ch. 8.1 - 4. A 95% confidence interval for a population mean...Ch. 8.1 - 5. Data were collected on the amount spent by 64...Ch. 8.1 - Travel Taxes. In an attempt to assess total daily...Ch. 8.1 - Prob. 7ECh. 8.1 - 8. Studies show that massage therapy has a variety...Ch. 8.1 - AARP reported on a study conducted to learn how...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 - 14. A simple random sample with n = 54 provided a...Ch. 8.2 - Prob. 15ECh. 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 - Prob. 19ECh. 8.2 - Prob. 20ECh. 8.2 - Prob. 21ECh. 8.2 - Prob. 22ECh. 8.3 - 23. How large a sample should be selected to...Ch. 8.3 - Prob. 24ECh. 8.3 - Prob. 25ECh. 8.3 - Prob. 26ECh. 8.3 - Prob. 27ECh. 8.3 - Prob. 28ECh. 8.3 - 29. Customers arrive at a movie theater at the...Ch. 8.3 - Prob. 30ECh. 8.4 - 31. A simple random sample of 400 individuals...Ch. 8.4 - 32. A simple random sample of 800 elements...Ch. 8.4 - Prob. 33ECh. 8.4 - 34. At 95% confidence, how large a sample should...Ch. 8.4 - The Consumer Reports National Research Center...Ch. 8.4 - 36. According to statistics reported on CNBC, a...Ch. 8.4 - 37. One of the questions on a survey of 1000...Ch. 8.4 - According to Thomson Financial, through last...Ch. 8.4 - Prob. 39ECh. 8.4 - For many years businesses have struggled with the...Ch. 8.4 - 41. Fewer young people are driving. In 1983, 87%...Ch. 8.4 - Prob. 42ECh. 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 - Russia has recently started a push for stronger...Ch. 8 - 48. The Health Care Cost Institute tracks health...Ch. 8 - A recent article reported that there are...Ch. 8 - 50. Mileage tests are conducted for a particular...Ch. 8 - Prob. 51SECh. 8 - Prob. 52SECh. 8 - 53. The National Center for Education Statistics...Ch. 8 - Prob. 54SECh. 8 - 55. The Pew Research Center has conducted...Ch. 8 - 56. A survey of 750 likely voters in Ohio was...Ch. 8 - The 2003 Statistical Abstract of the United States...Ch. 8 - 58. A well-known bank credit card firm wishes to...Ch. 8 - Prob. 59SECh. 8 - Prob. 60SECh. 8 - case Problem 1 Young Professional Magazine
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