A manufacturer claims that the mean lifetime, u, of its light bulbs is 45 months. The standard deviation of these lifetimes is 4 months. Thirty bulbs are seled at random, and their mean lifetime is found to be 44 months. Assume that the population is normally distributed. Can we conclude, at the 0.01 level of significance, that the mean lifetime of light bulbs made by this manufacturer differs from 45 months?

A manufacturer claims that the mean lifetime, u, of its light bulbs is 45 months. The standard deviation of these lifetimes is 4 months. Thirty bulbs are seled at random, and their mean lifetime is found to be 44 months. Assume that the population is normally distributed. Can we conclude, at the 0.01 level of significance, that the mean lifetime of light bulbs made by this manufacturer differs from 45 months?

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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