A cylinder and a cone have the same base and height, and the sum of their volumes is 72 cubic decimeters, what is the volume of the cone?
一个圆柱体和一个圆锥体等底等高，它们的体积之和是72立方分米，则圆锥体积为多少．
<gadget id="calculator">1 + 3</gadget>
<output>4</output>

<gadget id="calculator">72 / 4</gadget>
<output>18</output>

<result>18</result>