An office has four copying machines, and the random variable X measures how many of them are in use at a particular moment in time. Suppose that P(X = 0) = 0.08, P(X = 1) = 0.11, P(X = 2) = 0.27, and P(X = 3) = 0.33. Calculate the variance and standard deviation of the number of copying machines in use at a particular moment.

An office has four copying machines, and the random variable X measures how many of them are in use at a particular moment in time. Suppose that P(X = 0) = 0.08, P(X = 1) = 0.11, P(X = 2) = 0.27, and P(X = 3) = 0.33. Calculate the variance and standard deviation of the number of copying machines in use at a particular moment.

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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