Our department seminar room is lit by 7 light bulbs, controlled by a single switch. A minimum of 3 lights are needed for the room to be usable. Suppose the lifetime of the brand of light bulbs fitted is exponentially distributed with a mean of 400 hours. Assume a seminar lasts exactly 1 hour, and that the lights are switched on only during the seminar. What is the probability that after 500 seminars, exactly 3 bulbs do not need to be replaced? You may need to use a calculator. Give your answer rounded to 4 decimal places. Answer:

Our department seminar room is lit by 7 light bulbs, controlled by a single switch. A minimum of 3 lights are needed for the room to be usable. Suppose the lifetime of the brand of light bulbs fitted is exponentially distributed with a mean of 400 hours. Assume a seminar lasts exactly 1 hour, and that the lights are switched on only during the seminar. What is the probability that after 500 seminars, exactly 3 bulbs do not need to be replaced? You may need to use a calculator. Give your answer rounded to 4 decimal places. Answer:

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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