The River Clinic has two general practitioners who see patients daily. An average of six patients arrives at the clinic per hour. Each doctor spends an average of 15 minutes with a patient. The patients wait in a waiting area until one of the doctors is able to see them. However, because patients typically do not feel well when they come to the clinic, the doctors do not believe it is good idea to have a patient wait longer than an average of 15 minutes. Should this clinic add a third doctor, and, if so, will this alleviate the waiting problem?