The airport branch of a car rental company maintains a fleet of 50 SUVs.The interarrival time between requests for an SUV is 2.4 hours, on average,...

The airport branch of a car rental company maintains a fleet of 50 SUVs. The interarrival time between requests for an SUV is 2.4 hours, on average, with a standard deviation of 2.4 hours. There is no indication of a systematic arrival pattern over the course of the day. Assume that, if all SUVs are rented, customers are willing to wait until an SUV is available. An SUV is rented, on average, for 3 days, with a standard deviation of 1 day. 

What is the average number of SUVs parked in the company's lot?