1.A sandwich shop near campus has a special counter, open from 11 to 1pm, which is used exclusively for selling pre-made sandwiches. The clerk can handle a customer in about one minute. Customers arrive at the rate of 40 per hour on average. How long in minutes does a customer have to wait?
What is the average number of customers waiting in line?
What is the probability of there being two or more customers in the system?
Comments: find T1, N1, and 1-(Po+P1)