Answered: Construct a 95% confidence interval for…

Construct a 95% confidence interval for variance and decide if the manufacturer’s claim that variance=1 is valid. Assume the population of battery lives to be approximately normally distributed.

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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Find the 95% confidence interval for the variance and standard deviation for the time it takes a state police inspector to check a truck for safety if a sample of 21 trucks has a standard deviation of 5.2 minutes. Assume the variable is normally distributed.
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