# Waiting Line - Averages and Probability

See the attached file for full problem description.

Automobiles arrive at the drive-through window at the downtown Urbana, Illinois, post office at the rate of 4 every 10 minutes. The average service time is 2 minutes.

A. What is the average number of cars in the system?

B. What is the average number of cars waiting in the system?

C. What is the average number of cars waiting to receive service?

D. What is the average number of cars in line behind the customer receiving service?

E. What is the probability that there are no cars at the window?

F. What percentage of the time is the postal clerk busy?

G. What is the probability that there are exactly 2 cars in the system?

https://brainmass.com/statistics/quantative-analysis-of-data/waiting-line-averages-and-probability-120499

#### Solution Summary

A Word file contains the solutions to the waiting line problem, including averages, percentages and probabilities.