The School of Business Has 3 Fax Machines

Multiple Choice

The school of business has 3 fax machines.The toner in each machine needs to be changed after about 5 hours of use.There is one unit secretary who is responsible for the fax machine maintenance.It takes him 15 minutes to replace the toner cartridge.What is the average number of fax machines in the system?

A) .0142 fax machine
B) .1563 fax machine
C) .0249 fax machine
D) .2749 fax machine
E) None of the above