The volume difference between a cylinder and a cone with the same base and height is 30cm**3, what is the volume of the cone in cm**3.
等底等高的圆柱和圆锥体体积相差30cm**3，这个圆锥的体积是多少cm**3．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">30 / 2</gadget>
<output>15</output>

<result>15</result>