A computer repair shop has two work centers. The first center examines the computer to see what is wrong, and the second center repairs the computer. Let x1 and x2 be random variables representing the lengths of time in minutes to examine a computer (x1) and to repair a computer (x2). Assume x1 and x2 are independent random variables. Long-term history has shown the following times. Examine computer, x1: ?1 = 27.3 minutes; ?1 = 7.7 minutes Repair computer, x2: ?2 = 88.0 minutes; ?2 = 15.5 minutes Suppose it costs $1.50 per minute to examine the computer and $2.75 per minute to repair the computer. Then W = 1.50x1 + 2.75x2 is a random variable representing the service charges (without parts). Compute the mean, variance, and standard deviation of W. (Round your answers to two decimal places.)

A computer repair shop has two work centers. The first center examines the computer to see what is wrong, and the second center repairs the computer. Let x1 and x2 be random variables representing the lengths of time in minutes to examine a computer (x1) and to repair a computer (x2). Assume x1 and x2 are independent random variables. Long-term history has shown the following times. Examine computer, x1: ?1 = 27.3 minutes; ?1 = 7.7 minutes Repair computer, x2: ?2 = 88.0 minutes; ?2 = 15.5 minutes Suppose it costs $1.50 per minute to examine the computer and $2.75 per minute to repair the computer. Then W = 1.50x1 + 2.75x2 is a random variable representing the service charges (without parts). Compute the mean, variance, and standard deviation of W. (Round your answers to two decimal places.)

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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