cone has the same base area as a cylinder. It is known that the volume of the cylinder is 9 times that of the cone. The height of the cone is 7.8 cm. What is the height of the cylinder?
一个圆锥与一个圆柱底面积相等，已知圆柱的体积是圆锥的9倍，圆锥的高是7.8cm，圆柱的高是多少？
<gadget id="calculator">3 * 7.8</gadget>
<output>23.4</output>

<result>23.4</result>