15-23 Patients arrive at a clinic according to a Poison distribution at a rate of 30

patients per hour. The waiting room does not accommodate more than 14 patients.

Examination time per patient is exponential with mean rate 20 per hour.

a) Find the effective arrival rate at the clinic.

b) What is the probability that an arriving patient will not wait? Will find a

vacant seat in the room?

c) What is the expected waiting time until a patient is discharged from the

clinic?

15-31 In a bank customers arrive in a Poison stream with mean 36 per hour. The