From 11:00 AM to 12:00 Noon, 30 people arrive at a bank on average. When they enter they get in line to wait for a cashier. On average there are 3 customers in line waiting. On average customers spend 4 minutes with the cashier. When the customers leave the cashier, 90% immediately exit the bank and 10% go to the loan officer, where there is an average of 1/2 person waiting to see the loan officer. On average customers spend 15 minutes with a loan officer. 

a. Draw the process flow diagram for this process in either word or Excel (label all activities and buffers) 

b. Calculate the inventory, throughput rate and process time for each activity and buffer. 

c. State the average time that a customer who only goes to see the cashier spends in the bank including their time waiting. 

d. What is the average number of customers in the bank?