If the ratio of the heights of a cone and a cylinder with equal bases is 4:5, then the volume of the cone is equal to the volume of the cylinder.
等底的圆锥和圆柱，高的比是4：5，那么圆锥的体积是圆柱体积的多少．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(1/3) * (4/5)</gadget>
<output>4/15 = around 0.266667</output>

<result>4/15 = around 0.266667</result>