1. A computer room has three printers which can each print an average of five jobs per minute. The average number of jobs entering a single queue for the three machines is twelve per minute. Assuming the queue is m|m|3; (a) What is the idle time if any for the printers? (b) What is the average time a job will spend in the printers' queue? (c) What is the average time a job is in the system? (d) What is the average number of jobs in the system? (e) If the three slow printers were replaced with a single fast printer, working at an average of fifteen jobs per minute, what will be the average time a job will spend in the system?
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The arrival rate is 12 jobs per minute. Since the service rate is greater than the arrival rate, the printers will not be idle. So, the idle time is 0. Show more…
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