Suppose the height of a cylinder is equal to its radius. the cylinder can fit inside a square prism, as shown below. The cross-sectional areas are still the same and the ratio of the circle to the area of the square is still pi/4. Complete the derivation of the formula for a cylinder
whose height is equal to its radius.
The prism's volume is the area of the base,
times the height,
Since the ratio of the areas is then the volume of
the cylinder is times the volume of the prism.
V = (4x2), or