A Local Post Office Uses 10,000 Boxes a Year

Essay

A local post office uses 10,000 boxes a year.Carrying costs are 15 cents per box a year,and ordering costs are $20 per order.The following price schedule applies.What is the optimal order quantity?
$$\begin{array} { l c } \text { Number of Boxes } & \text { Price per Box } \\0 - 199 & \$ 1.50 \\200 - 299 & \$ 1.25 \\300 - 399 & \$ 1.10 \\400 \text { or more } & \$ 1.00\end{array}$$