The records of 100 postal employees who volunteered for a study, showed that the average time these employees had worked for the postal service was x̅=8 years. Assume that we know that the standard deviation of the population of time postal service employees have spent with the postal service is approximately normal with a standard deviation of σ=5 years. A 95% confidence interval for the meantime μ the population of postal service employees have spent with the postal service is?

The records of 100 postal employees who volunteered for a study, showed that the average time these employees had worked for the postal service was x̅=8 years. Assume that we know that the standard deviation of the population of time postal service employees have spent with the postal service is approximately normal with a standard deviation of σ=5 years. A 95% confidence interval for the meantime μ the population of postal service employees have spent with the postal service is?

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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