A Recently-Divorced Father Checks the Level of Boil and Serve

Short Answer

A recently-divorced father checks the level of Boil and Serve macaroni and cheese in his pantry the last day of every month. He uses an average of 20 boxes per month (his reorder lead time)with a standard deviation of 5 boxes and wants to avoid the embarrassment and deprivation of a stockout 99% of the time. Lead time is essentially zero since he can pick up a box on the way home from work each day. What should his restocking level be?