Question

Cheryl 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 carboard. How much will be left over?

(Hint: Find the surface area first to find how much will be left over)

(1 point)
Responses

54 inches squared
54 inches squared

426 inches squared
426 inches squared

446 inches squared
446 inches squared

406 inches squared

Answer 1

Let's first find the surface area of the box.

Surface Area = 2lw + 2lh + 2wh
Surface Area = 2(10*9) + 2(10*7) + 2(9*7)
Surface Area = 180 + 140 + 126
Surface Area = 446 square inches

Now, since Cheryl purchased 500 square inches of cardboard but the surface area of the box is only 446 square inches, the amount left over is:
500 - 446 = 54 square inches

Therefore, the correct answer is: 54 inches squared.