# Waiting line models

• Nov 23rd 2008, 07:35 PM
chloe625
Waiting line models
Hi,
Can someone tell me the way to find part b-e? I have all the operating characteristics of the model calculated, see the attached excel file. I just can't figure out how to calculate the other parts of the problem.

Marty’s Barber Shop has one barber. Customers arrive at the rate of 2.2 customers per hour, and haircuts are given at the average rate of 5 per hour. Use the Poisson arrivals and exponential service times model to answer the following questions:

a. What is the probability that there are no customers in the system?
b. What is the probability that 1 customer is receiving a haircut and no one is waiting?
c. What is the probability that 1 customer is receiving a haircut and 1 customer is waiting?
d. What is the probability that 1 customer is receiving a haircut and 2 customers are waiting?
e. What is the probability that more than two customers are waiting?
f. What is the average time a customer waits for service?

Much appreciated!

Chloe