An insurance company is trying to estimate the average number of sick days that fulltime food service workers use per year. A pilot study found the population standard deviation to be 2.5 days. How large a sample must be selected if the company wants to be 95% confident of getting an interval that contains the true mean with a margin of error of 2 days?

An insurance company is trying to estimate the average number of sick days that fulltime food service workers use per year. A pilot study found the population standard deviation to be 2.5 days. How large a sample must be selected if the company wants to be 95% confident of getting an interval that contains the true mean with a margin of error of 2 days?

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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