Question

A bank teller can handle 40 customers an hour and customers arrive every six minutes. what is the average time a customer spends waiting in line?

a. 15 seconds b. 0.40 minutes c. 1.25 minutes d. 30 seconds

Answer 1

The average time a customer spends waiting in line can be found using Little's Law. In this case, the average time a customer spends waiting in line is 0.25 minutes, which is equivalent to 15 seconds. The correct option is A.

Step-by-step explanation:

The average time a customer spends waiting in line can be found using Little's Law, which states that the average time a customer spends in the system (waiting + service time) is equal to the average number of customers in the system divided by the arrival rate (customers per hour). In this case, the arrival rate is 40 customers per hour. We can calculate the average time a customer spends in line as follows:

1. Convert the arrival rate from customers per hour to customers per minute: 40 customers per hour = 40/60 customers per minute = 0.67 customers per minute.
2. Calculate the arrival rate for each customer: 1 customer arrives every 6 minutes, so the arrival rate per customer is 1/6 customers per minute = 0.17 customers per minute.
3. Divide the arrival rate per customer by the arrival rate: 0.17 customers per minute / 0.67 customers per minute = 0.25 minutes per customer.

Therefore, the average time a customer spends waiting in line is 0.25 minutes, which is equivalent to 15 seconds.