Complete question is;
A campus deli serves 300 customers over its busy lunch period from 11:30 am to 1:30 pm. A quick count of the number of customers waiting in line and being served by the sandwich makers shows that an average of 10 customers are in process at any point in time. What is the average amount of time that a customer spends in process?
Answer:
4 minutes
Step-by-step explanation:
For this question, we will apply Little's law which is is a theorem that determines the average number of items in a stationary queuing system, based on the average waiting time of an item within a system and the average number of items arriving at the system per unit of time.
The formula for the law is:
Inventory = flow rate × flow time.
We are given;
Inventory = 300 customers
flow time is from 11: 30am to 1:30pm which is 2 hours = 120 minutes
Flow rate = 300/120 = 2.5 persons/minute
Now, Making flow rate the subject of the formula earlier given, we have;
flow rate = inventory/ flow time
Flow time is the time each person spends in the process
Thus, plugging in the relevant values, we get ;
We are told that an average of 10 customers are in process at any point in time.
Thus;
Average flow time = average inventory/flow rate = 10/2.5 = 4 minutes
