A random sample of 25 employees for the retailer showed a sample meanof 9.2 minutes and a standard deviation of 2 minutes. Assume that the time spent by employees onpersonal phone calls is normally distributed. Let u denote the mean time spent by employees onpersonal phone calls.(a) Find the 95% confidence interval for µ.(b) An employee group for a national retailer claims that the mean time spent by employees onpersonal phone calls is less than 10 minutes per day. Specify the correct null and alternativehypotheses you would use to investigate the employee group's claim.(c) Find the value of the standardized test statistic.(d) Find the rejection region at a-0.05 and state your conclusion in the context of the problem.

Given information: The sample size, the sample mean, and the standard deviation are n=25, x¯=9.2,…

Answered: A random sample of 25 employees for the…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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