In a sample of 80 light bulbs, the mean lifetime was 1217 hours with a standard deviation of 54 hours. How many light bulbs must be sampled so that a 95% confidence interval will specify the mean wall thickness to within ±8 hours? (Round up the final answer to the nearest integer.) The number of light bulbs that must be sampled is

In a sample of 80 light bulbs, the mean lifetime was 1217 hours with a standard deviation of 54 hours. How many light bulbs must be sampled so that a 95% confidence interval will specify the mean wall thickness to within ±8 hours? (Round up the final answer to the nearest integer.) The number of light bulbs that must be sampled is

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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