On average, 4 customers are waiting in line to be served in a local UPS store. The average waiting time is 5 minutes. The probability distributions that describe arrival and service times are unknown. What is the arrival rate per hour?
A) 48 customers
B) 0.8 customers
C) 1.2 customers
D) 100 customers
E) 20 customers

Question

Quizplus · Accepted Answer

Using Little's Law, L = λW, where L is the average number of customers in the system (4), W is the average waiting time (5 minutes or 1/12 hour), and λ is the arrival rate. Solving for λ gives λ = L/W = 4 / (1/12) = 48 customers per hour.

On Average, 4 Customers Are Waiting in Line to Be