Orchid wants to retile your bathroom floor, which has an area of 40 square feet. she is deciding between two types of custom tiles. the square tile is 0.5 foot by 0.5 foot and costs $0.45 per tile. the rectangular tile is 2 feet by 0.25 foot and costs $0.80 per tile.
which tile should orchid choose to minimize costs? explain.

a. she should choose the square tiles because the total cost will be $8 less.
b. she should choose the rectangular tiles because the total cost will be $8 less.
c. she should choose the square tiles because the total cost will be $14 less.
d. she should choose the rectangular tiles because the total cost will be $14 less.

The area of the square title is 0.25 square feet (0.5 x 0.5 ft^2), while the area of the rectangular title is 0.5 square feet (2 x 0.25 ft^2).
In getting the number of tiles required for the floor, the floor area is divided by the area of the tile. It would then take 160 square tiles or 80 rectangular tiles.
The price for the  retiling is simply the product of the number of tiles required and the price of the specific tile. If square tiles are to be used, Orchid would have to spend $72, while $64 would be spent if rectangular tiles were used. 
The spending if  rectangular tiles were used is $8 cheaper than that if square tiles were to be used. This makes the answer of the problem B.