According to a report from a business intelligence company, smartphone owners are using an average of 22 apps per month. Assume that number of apps used per month by smartphone owners is normally distributed and that the standard deviation is 7. If you select a random sample of 25 smartphone owners, what is the probability that the sample mean is between 21.5 and 22.5?

According to a report from a business intelligence company, smartphone owners are using an average of 22 apps per month. Assume that number of apps used per month by smartphone owners is normally distributed and that the standard deviation is 7. If you select a random sample of 25 smartphone owners, what is the probability that the sample mean is between 21.5 and 22.5?

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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