Stacey needs to buy some cardboard to build a box 10 inches long, 9 inches wide, and 7 inches high. If she purchases 500 square inches of cardboard, how much will be left over?
First, let's calculate the total surface area of the box:
2*(10*9) + 2*(10*7) + 2*(9*7) = 180 + 140 + 126 = 446 square inches
Since Stacey purchases 500 square inches of cardboard, she will have 500 - 446 = 54 square inches left over.