the men's department of a large store employs one tailor for customer fitting, the number of customers requiring fitting appear to follow a poison distribution with mean arrival rate of 24per/hr, customers are fitted on a FCFS basic and they are always willing to wait for the tailor's service. the time it takes to fit a customer appear to be exponentially distributed with a mean of 2mins.
1. what is the average number of customers in the fitting room
2. how much time should a customer expect to spend in the fitting room
3. what percentage of the time is the tailor idle
4. what is the probability that a customer will wait more than 10mins for the tailor's service.