3. A company receives shipments of batteries and before taking the delivery test using a ra sample of 64 batteries. For one shipment, a sample mean lifetime of 49.5 hours was foun company is concerned that the true life for all batteries in the shipment not be less th hours. It is assumed that the population is normal with standard deviation of 5 hours. a) Construct hypothesis and test it at the 0.01 significance level b) Find 99 percent confidence interval

3. A company receives shipments of batteries and before taking the delivery test using a ra sample of 64 batteries. For one shipment, a sample mean lifetime of 49.5 hours was foun company is concerned that the true life for all batteries in the shipment not be less th hours. It is assumed that the population is normal with standard deviation of 5 hours. a) Construct hypothesis and test it at the 0.01 significance level b) Find 99 percent confidence interval

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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