How do you convert 66 inches long by 66 inches wide by 29 inches high to cubic feet?

Since you want an answer in cubic feet you must convert all the variables to feet;

divide all the variables by 12" which is one foot.

This is a question of volume, which is in cubic feet.

use the formula for volume of a rectangle which is:

V = LWH

Where L is length, W is width, H is hight.

Convert your dimensions to feet

L = 2.75' = 33"/12"

W = 1.5' = 18"/12"

H = 1.17' = 14"/12"

use the formula

V = LWH replace the letters with the values

V = 2.75 * 1.5 * 1.17

V = 4.83 cubic ft

If you want gallons of liquid (water) multiply 7.48 which is 1 cubic ft of water

the G = 4.83 * 7.48

G = 36.13 gallons