Patients arrive at a clinic at the rate of 19.4 per hour. Data analysis shows that their interarrival times are exponentially distributed.

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Patients arrive at a clinic at the rate of 19.4 per hour. Data analysis shows that their interarrival times are exponentially distributed. Service times at the reception counter are also found to be exponentially distributed, averaging 12.5 minutes per customer. With 5 receptionists, the average time for a customer to wait in line will be approximately