A business school is considering replacing its copy machine with a faster model. Past records show that the average student arrival rate is 24 per hour, Poisson dis-tributed, and that the service times are distributed exponentially. The selection committee has been instructed to consider only machines that will yield an average turnaround time ( i. e., expected time in the system) of 5 minutes or less. What is the smallest processing rate per hour that can be considered?