Takheela plans to ship a dollhouse in a box that is 30 inches along each edge. The dollhouse measures 24 inches wide, 20 inches long, and 28 inches high. How much foam packing material (in cubic inches) will she need? What is the approximate side length of the cubic box that holds only the packing material?
Are you assuming that the dollhouse has a flat roof rather than a peaked one? I will guess so.
Volume of house = 24*20*28
Volume of box = 30^3
Subtract house from box to get foam volume. Cube root of that is the side length of box for packing material.