Q2: The life of a semiconductor laser at a constant power is normally distributed with a mean of 7500 hours and a standard deviation of 500 hours. a. What is the probability that a laser fails before 5500 hours? b. What is the probability that a laser lasts more than 8250 hours? c. What is the life in hours that 95% of the lasers exceed?

Q2: The life of a semiconductor laser at a constant power is normally distributed with a mean of 7500 hours and a standard deviation of 500 hours. a. What is the probability that a laser fails before 5500 hours? b. What is the probability that a laser lasts more than 8250 hours? c. What is the life in hours that 95% of the lasers exceed?

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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