accounting

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Alpha Walk-in Clinic operates as a single channel single server system.  On Tuesdays, its average arrival rate per hour is 7.0.  Analysis indicates that its service rate is 8.5 patients per hour.  Using queuing theory describe this service system.  What is:

1. The probability that the clinic is idle � no person waiting or being served?
2. The average number of patients in the system?
3. The average time (hours) a patient spends in the system (waiting + service time)?
4. The average number of patients in the queue waiting for service?
5. The average time (hours) a patient spends in the queue waiting?
6. The probability that the patient, upon arrival, must wait?