A particular pipeline booster unit that operates continuously on a 24-hour basis requires service at exponential time intervals with mean time between breakdowns equal to 20 hours. A repairperson can service a broken booster on the average in 10 hours with exponential service time. At a station with 10 boosters and two repairpersons on duty at all times, each repairperson draws a salary of $7.00 an hour. Pipeline schedule losses are estimated to be $15.00 per hour per broken pump. The company is considering hiring an additional repairperson.