Customers enter the camera department of a store at the average rate of five per hour. The department is staffed by one employee, who takes an average of 8.0 minutes to serve each arrival. Assume this is a simple Poisson arrival, exponentially distributed service time situation.
a. How long would a customer expect to spend in the camera department (total time)?
b. What is the probability that there are more than two people in the camera department (excluding the clerk)?
c. Another clerk has been hired for the camera department who also takes an average of 8.0 minutes to serve each arrival. How long would a customer expect to spend in the department now? (average total time) in minutes.