Prob-4The lighting department of a city has installed 2000 electric lamps with an average life of 10,000 h and a standard deviation of 500 h.After what period of lighting hours would we expect 65.54% of the lamps to fail? Assume life of lamps are normally distributed.Sol:

Solution-: Given: μ=10000,σ=500 We want to find x such that, P[X<x]=0.6554

Answered: The lighting department of a city has…

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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The lighting department of a city has installed 2000 electric lamps with an average life of 10,000 h and a standard deviation of 500 h. After what period of lighting hours would we expect 65.54% of the lamps to fail? Assume life of lamps are normally distributed.