My son, who is in secondary school, needs to make a box with the inside dimensions of 1.25 cubic feet. It's supposed to be more in the shape of a rectangle than a square. I would like to know the equation to use to find the inside dimensions of a box if I know how many cubic feet (or inches) I need the inside to be. Thank you for your help! Paula Hi Paula, The volume of a box is length width height so any box where the product of the length, width and height (all measures in feet) is 1.25 will do. It is probably easier to do this in inches. A box that is 1 foot by 1 foot by 1 foot has a volume of 1 cubic foot. Such a box is 12 inches by 12 inches by 12 inches and hence its volume is 12 12 12 = 1728 cubic inches. Thus 1728 cubic inches = 1 cubic foot Hence 1728 1.25 = 2160 cubic inches = 1.25 cubic feet Thus you want a box so that the product of the length, width and height (all measures in inches) is 2160. For example if the box is 24 inches long and 12 inches wide then  2160/24 x 12 = 7.5, so it would have to be 7.5 inches high. Cheers, Penny Go to Math Central To return to the previous page use your browser's back button.