The reduced area is equal to the lateral area of a cylinder with a height of 2 cm, so 12.56 divided by 2 is equal to 6.28 cm, which is the circumference of the bottom surface. Divide the perimeter of the bottom surface by 6.28, divide it by 2 and then divide it by 3. 14= 1 cm, which is the radius, and then you can calculate the volume: 3. 14 * 1 *.