Extended constructed response

Question

Stella received a package in the shape of a rectangular prism. The box has a length of 2 1/2 feet, a width of 1 1/2 feet and a height of 4 feet. Stella wants to cover the box with wrapping paper. How much will she need and why.

Answer 1

Hi Melanie!

Sounds to me like this question is looking for the surface area of the package–the amount of wrapping paper she needs to cover the box will be equal to the surface area of the box itself.

If you recall, a rectangular prism has 6 sides. As the problem statement says, length L = 2.5, width W = 1.5 and height H = 4.

The equation for the surface area, A, of a rectangular prism is

A = 2 * (L*W + L*H + W*H)

This is just the area of each of the sides added up.

Plugging in, we get

A = 2 * (2.5 * 1.5 + 2.5 * 4 + 1.5 * 4) = 39.5 square feet