premise: The amount ordered should be sufficient so that the number of units on hand plus those that are on order equal some  maximum  stocking quantity, S.13 For a particular item, our store buyer may reorder when the inventory level falls below s equals 4 units, in a quantity that brings the current inventory up to S equals 8 units.
hypothesis: The amount ordered should be sufficient so that the number of units on hand equal roughly more than some of the maximum stocking quanitity.