Problem
A small oil change shop uses an average of 80 liters of 5W40 synthetic oil per day. Usage tends to be normally distributed with a standard deviation of 8 liters per day. Lead time is four days, and the desired service level is 92 percent. What amount of safety stock is appropriate under each of these conditions?
a. Oil is reordered every 45 days.
b. A fixed order size of 2400 litres is used.