Cherese 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?
a. 426 in.^2
b. 54 in. ^2
c. 406 in. ^2
d. 446 in. ^2
c. 406 in. ^2
To find the total surface area of the box, we need to find the area of each of the six sides and add them together.
- The top and bottom of the box (2 sides) will have an area of 10 inches x 9 inches = 90 square inches each.
- The front and back of the box (2 sides) will have an area of 10 inches x 7 inches = 70 square inches each.
- The two sides of the box (2 sides) will have an area of 9 inches x 7 inches = 63 square inches each.
Adding all the areas together:
90 + 90 + 70 + 70 + 63 + 63 = 446 square inches
Since Cherese purchased only 500 square inches of cardboard, the amount left over will be:
500 - 446 = 54 square inches (leftover)