A car wash is trying to determine how long the average line for a wash will be. The probability distributions that describe arrival and service times are unknown. If 10 cars arrive each hour and must wait 12 minutes in the line, how long will the line be, on average?
A) 120 cars
B) 2 cars
C) 1 car
D) 0.83 cars
E) 5 cars

Question

Quizplus · Accepted Answer

Given that 10 cars arrive each hour and each car waits 12 minutes in line, we can calculate the average line length as follows: 10 cars/hour * 12 minutes = 120 car-minutes per hour. Since there are 60 minutes in an hour, this equates to 2 cars in line on average (120 car-minutes / 60 minutes per hour = 2 cars).

A Car Wash Is Trying to Determine How Long the Average