Cherese needs to buy some cardboard to build a box 10 inches long, 9 inches wide, and 7 inches high. If she purchases 500 in.² of cardboard, how much will be left over?

Answer 1

First, calculate the surface area of the box:

2(10*9) + 2(10*7) + 2(9*7) = 180 + 140 + 126 = 446 in.²

Subtract the surface area of the box from the total amount of cardboard purchased:

500 - 446 = 54 in.²

Cherese will have 54 in.² of cardboard left over.