Cut a cylinder with a height of 10 cm vertically along the height, divide it into several parts, and assemble it into an approximate cuboid with the same volume. The perimeter of the bottom of the cuboid with the same area is larger than that of the cylinder 20 cm. What is the volume of the original cylinder?
把一个高是10厘米的圆柱体沿着高垂直切开，分成若干份，拼成一个和它体积相等的近似长方体，这个面积不变的长方体的底面周长却比圆柱的底面周长增加了20厘米．原来这个圆柱体的体积是多少？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 ** 2</gadget>
<output>100</output>

<gadget id="calculator">3.14 * 100 * 10</gadget>
<output>3_140</output>

<result>3_140</result>