Question

Gavin must paint a cube shaped box the edge length is 2 1/2 feet.

Answer 1

Surface area of the box = 37.5 square feet

Solution:

Edge length of the cube (a) = $2\frac{1}{2}$ ft

Convert mixed fraction into improper fraction.

$2\frac{1}{2}=\frac{2\times2 + 1}{2}=\frac{5}{2}$

Surface area of the cube = 6a²

                                          $=6\left(2\frac{1}{2}\right)^2$

                                          $=6\left(\frac{5}{2}\right)^2$

                                          $=6\left(\frac{25}{4}\right)$

                                          = 37.5 square feet

Surface area of the box = 37.5 square feet