A cylinder and a cone have equal volumes and equal bases. The height of the cylinder is 9. What is the height of the cone?
一个圆柱与一个圆锥等体积，等底面，圆柱的高是9，圆锥的高是多少．
<gadget id="calculator">9 * 3</gadget>
<output>27</output>

<result>27</result>