The volume of a cone is 12 cubic decimeters, the height is 3 decimeters, what is the area of the base?
一个圆锥的体积是12立方分米，高是3分米，底面积是多少．
<gadget id="calculator">3 / 3</gadget>
<output>1</output>

<gadget id="calculator">12 * 1</gadget>
<output>12</output>

<result>12</result>