Probability and Statistics for Engineering and the Sciences
9th Edition
ISBN: 9781305251809
Author: Jay L. Devore
Publisher: Cengage Learning
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Chapter 7.1, Problem 6E
On the basis of extensive tests, the yield point of a particular type of mild steel-reinforcing bar is known to be
- a. Assuming this to be the case, if a sample of 25 modified bars resulted in a sample average yield point of 8439 lb, compute a 90% CI for the true average yield point of the modified bar.
- b. How would you modify the interval in part (a) to obtain a confidence level of 92%?
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Chapter 7 Solutions
Probability and Statistics for Engineering and the Sciences
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