If the circumference of the base of a cone is twice the circumference of the base of the cylinder, and the ratio of the height of the cylinder to the height of the cone is 3:4, then the volume of the cylinder is equal to the volume of the cone.
一个圆锥的底面周长是圆柱底面周长的两倍，且圆柱的高与圆锥的高的比是3：4，那么圆柱的体积是圆锥体积的多少．
<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">4 * 4</gadget>
<output>16</output>

<gadget id="calculator">9 / 16</gadget>
<output>9/16 = around 0.5625</output>

<result>9/16 = around 0.5625</result>