The natural logarithm of the lifetime (i.e., take the natural log of the lifetime, in hours) of acertain type of bulb is found to be normally distributed with a mean of 13 hours and astandard deviation of 1.5 hours. What is the probability that:(a) One randomly selected bulb of this type survives 2.5 years of use.(b) At least one in two of this type of bulb will survive 2.5 years of use.(c) How many bulbs of this type shall be installed in a room to guarantee 99.99% reliabilitythat at least one can light the room after 3 years?

Let X be the lifetime of a considered type of bulb. The distribution of X can be stated as Y =…

Answered: The natural logarithm of the lifetime…

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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