The Ace Hardware store expects to sell 1,500 electric garbage disposal systems in the coming year. Demand for this product is fairly stable over the year. It costs $20 to place an order for these systems and the company assumes a 20% annual holding cost on inventory. The following price structure applies to Ace’s purchase of this product:
0 to 499= $35 a unit
500 to 999= $33 a unit
1000+= $31 a unit
ie. if it orders 650, it pays $33 per system; and if it orders 1200, it pays $31 per system.
Formulate an equation with variables and constraints.