Question: A construction company owns six backhoes, which each break down, on average, once every 10 working days, according to a Poisson distribution. The mechanic assigned to keeping the backhoes running is able to restore a backhoe to sound running order in 1 day, according to an exponential distribution.
(a) How many backhoes are waiting for service, on average?
(b) How many are currently being served?
(c) How many are in running order, on average?
(d) What is the average waiting time in the queue?
(e) What is the average wait in the system?