Two square pyramids have the same volume. For the first pyramid, the side length of the base is 15 in., and the height is 18 in. The second pyramid has a height of 54 in. What is the side length of the base of the second pyramid?

Volume for a square pyramid uses the formula V = a^2 x h/3

Volume for the first pyramid = 15^2 x 18/3 = 225 x 6 = 1350 cubic inches.

The second pyramid has the same volume, so we can use the volume from the first one to solve for the side length:

Second pyramid: 1350 = a^2 x 54/3

1350 = a^2 x 18

a^2 = 1350 / 18

a^2 = 75

a = √75 = 8.66 inches