1,000 light bulbs with a mean life of 120 days are installed in a new fac-tory. Their length of life is normally distributed with standard deviation 20 days. () Howmany bulbs will expire in less than 90 days ? (i) If it is decided to replace all the bulbstogether, what iniervals should be allowed between replacements if not more than 10 per-cent should expire before replacement ?

GivenMean(μ)=120standard deviation(σ)=20No.of light bulbs = 1000

Answered: 1,000 light bulbs with a mean life of…

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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