Understanding Basic Statistics
7th Edition
ISBN: 9781305254060
Author: Charles Henry Brase, Corrinne Pellillo Brase
Publisher: Cengage Learning
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Textbook Question
Chapter 8.1, Problem 21P
Confidence Intervals:
(a) Compute a 95% confidence interval for µ based on a sample of size 49. What is the value of the margin of error?
(b) Compute a 95% confidence interval for µ based on a sample of size 100. What is the value of the margin of error?
(c) Compute a 95% confidence interval for µ based on a sample of size 225. What is the value of the margin of error?
(d) Compare the margins of error for parts (a) through (c). As the sample size increases, does the margin of error decrease?
(e)Critical Thinking Compare the lengths of the confidence intervals for parts (a) through (c). As the sample size increases, does the length of a 90% confidence interval decrease?
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Chapter 8 Solutions
Understanding Basic Statistics
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