At a busy lunch hour, customers arrive at a cafeteria checkout lane at a rate of 129 customers per hour. Once a customer has arrived at the front of the line (after some waiting, if need be), the average time to complete the checkout process takes about 20 seconds.

What would be the service rate in hours (i.e., how many customers, on average, can this system serve per hour)? Round your answer to the nearest fourth decimal point.

What is the system utilization?

What is the probability that a customer will arrive at the checkup counter without having to wait at all?

What would be the average number of customers waiting in line?

How many minutes will a customer, on average, be waiting in line before reaching the front of the line?