Statistics for Engineers and Scientists - With Access
4th Edition
ISBN: 9781259275975
Author: Navidi
Publisher: MCG
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Textbook Question
Chapter 5.2, Problem 12E
In a random sample of 150 customers of a high-speed internet provider, 63 said that their service had been interrupted one or more times in the past month.
- a. Find a 95% confidence interval for the proportion of customers whose service was interrupted one or more times in the past month.
- b. Find a 99% confidence interval for the proportion of customers whose service was interrupted one or more times in the past month.
- c. Find the
sample size needed for a 95% confidence interval to specify the proportion to within ±0.05. - d. Find the sample size needed for a 99% confidence interval to specify the proportion to within ±0.05.
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Chapter 5 Solutions
Statistics for Engineers and Scientists - With Access
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