cylinder and a cone have the same base and height, the volume of the cylinder is 90 cubic centimeters, what is the volume of the cone in cubic centimeters?
等底等高的一个圆柱和一个圆锥，圆柱的体积是90立方厘米，则圆锥的体积是多少立方厘米．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">90 * (1/3)</gadget>
<output>30</output>

<result>30</result>