A cylinder and a cone have the same base and height, and the difference in volume is 21 cubic centimeters. What is the volume of the cone in cm**3.
一个圆柱和一个圆锥等底等高，体积相差21立方厘米，圆锥的体积是多少cm**3．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">21 / 2</gadget>
<output>21/2 = around 10.5</output>

<result>21/2 = around 10.5</result>