EBK STATISTICS FOR ENGINEERS AND SCIENT
4th Edition
ISBN: 9780100274389
Author: Navidi
Publisher: YUZU
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Textbook Question
Chapter 5.1, Problem 9E
In a sample of 80 ten-penny nails, the average weight was 1.56 g and the standard deviation was 0.1 g.
- a. Find a 95% confidence interval for the mean weight of this type of nail.
- b. Find a 98% confidence interval for the mean weight of this type of nail.
- c. What is the confidence level of the interval (1.54, 1.58)?
- d. How many nails must be sampled so that a 95% confidence interval specifies the mean to within ±0.01 g?
- e. Approximately how many nails must be sampled so that a 98% confidence interval will specify the mean to within ±0.01 g?
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Chapter 5 Solutions
EBK STATISTICS FOR ENGINEERS AND SCIENT
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