Bill Ding plans to build a new hardware store. He buys a rectangular lot that is 50 ft by 200 ft, the 50-foot dimension being along the street. The store is to have an area of 4000 square feet. Construction costs $100 per linear foot for the part of the store along the street and only $80 per linear foot for the parts along the sides and back. To what dimensions should Bill build the store in order to minimize the construction coast?

Answer 1

Use the entire 200- ft dimension to
minimize cost:

200W = 4000 SQ FT,
W = 4000 / 200 = 20 FT.

L * W = 200 * 20.