An assembly station is asked to process 100 circuit boards per hour. It takes 20 minutes to receive the necessary components from the previous workstation. Completed circuit boards are placed in a rack that will hold 10 boards. The rack must be full before it is sent on to the next workstation. If the factory uses a safety factor of 10%, how many kanbans would be needed in each case? (Round answers to 0 decimal places, e.g. 25.)
a. Demand is increased to 200 circuit boards per hour. How many kanbans?
b. The lead time for components is increased to 30 minutes. How many kanbans?
c. The rack size is halved. How many kanbans?
d. The safety factor is increased to 20%. How many kanbans?