A general-purpose auto-repair garage has one mechanic who specializes in muffler installations. Customers seeking service arrive at an average rate of 2 per hour, with a Poisson distribution. The average time to install a muffler is 20 minutes, with negative exponential distribution. a) On arrival at the garage, how many customers should one expect to find in the system? b) The management is interested in adding another mechanic when the customer’s average time in the system exceeds 90 minutes. If business continues to increase, at what arrival rate per hour will an additional mechanic be needed?

A general-purpose auto-repair garage has one mechanic who specializes in muffler installations. Customers seeking service arrive at an average rate of 2 per hour, with a Poisson distribution. The average time to install a muffler is 20 minutes, with negative exponential distribution. a) On arrival at the garage, how many customers should one expect to find in the system? b) The management is interested in adding another mechanic when the customer’s average time in the system exceeds 90 minutes. If business continues to increase, at what arrival rate per hour will an additional mechanic be needed?

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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