Repair calls are handled by one repairman at a photocopy sho

Repair calls are handled by one repairman at a photocopy shop. Repair time, including travel time, is exponentially distributed, with a mean of 1 hour and 20 minutes per call. Requests for copier repairs come in at a mean rate of five per eight-hour day (assume Poisson distribution). Determine:

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( ^ how do you determine these?)

A. The average number of customers awaiting repairs.
B. System utilization.
C. The amount of time during an eight-hour day that the repair man is not on call.
D. The probability of two or more customers in the system.

Solution