a. Suppose that a random sample of 41 state college students is asked to measure the length of their right foot in centimeters. A 95% confidence interval for the mean foot length for students at this university turns out to be (21.709, 25.091). If we now calculated a 90% confidence interval, would the new confidence interval be wider than or narrower than or the same as the original? b. Suppose two researchers want to estimate the proportion of American college students who favor abolishing the penny. They both want to have about the same margin of error to estimate this proportion. However, Researcher 1 wants to estimate with 95% confidence and Researcher 2 wants to estimate with 99% confidence. Which researcher would need fewer students for her study in order to obtain the desired margin of error? The answer is Researcher c. A 95% confidence interval for the mean reading achievement score for a population of third grade students is (55, 65). The margin of error of this interval is what whole number?

a. Suppose that a random sample of 41 state college students is asked to measure the length of their right foot in centimeters. A 95% confidence interval for the mean foot length for students at this university turns out to be (21.709, 25.091). If we now calculated a 90% confidence interval, would the new confidence interval be wider than or narrower than or the same as the original? b. Suppose two researchers want to estimate the proportion of American college students who favor abolishing the penny. They both want to have about the same margin of error to estimate this proportion. However, Researcher 1 wants to estimate with 95% confidence and Researcher 2 wants to estimate with 99% confidence. Which researcher would need fewer students for her study in order to obtain the desired margin of error? The answer is Researcher c. A 95% confidence interval for the mean reading achievement score for a population of third grade students is (55, 65). The margin of error of this interval is what whole number?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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