Question

Helen has 48 cubic inches of clay to make a solid square right pyramid with a base edge measuring 6 inches.

A solid right pyramid with a square base has a base edge measuring 6 inches.

Which is the slant height of the pyramid if Helen uses all the clay?

3 inches
4 inches
5 inches
6 inches

Answer 1

Volume = (1/3)(base area)(height) = (1/3)(6^2)h = 12h.
Set 12h = 48 ⇒ h = 4 in.
Slant height = sqrt(h^2 + (half base)^2) = sqrt(4^2 + 3^2) = sqrt(25) = 5 in.

Answer: 5 inches.