A Crew of Mechanics at the Highway Department Garage Repair

Essay

A crew of mechanics at the Highway Department Garage repair vehicles that break down at an average of λ = 7 vehicles per day (approximately Poisson in nature). The mechanic crew can service an average of μ = 11 vehicles per day with a repair time distribution that approximates an exponential distribution.
(a) What is the utilization rate for this service system?
(b) What is the average time before the facility can return a breakdown to service?
(c) How much of that time is spent waiting for service?
(d) How many vehicles are likely to be waiting for service at any one time?