The manufacturer of a certain brand of automobiles component claims that mean life of these component is 70 months. An independent agency wants to check this claim and took a randor sample of 40 components and found that the mean life for this sample is 67 months with a standard deviation of 5 months. At 5% LOS, can we conclude that the mean life of these component is less than 70 months?

The manufacturer of a certain brand of automobiles component claims that mean life of these component is 70 months. An independent agency wants to check this claim and took a randor sample of 40 components and found that the mean life for this sample is 67 months with a standard deviation of 5 months. At 5% LOS, can we conclude that the mean life of these component is less than 70 months?

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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