Why do we Divide the volume formula for a rectangular prism by three.

The volume of a pyramid is 1/3 * (the area of the base) * (the height). I do not know an intuitive way to show why the fraction 1/3 appears.

If the pyramid has a square base with side length x and the height of the pyramid is x/2 then you can put six of these pyramids together to form a box or cube.

1/6 x^3 = 1/3 * x^2 * (1/2 x) = 1/3 * (the area of the base) * (the height). Hopefully this gives you some info if not just ask and i can give you a much simpler answer