If a conical container with a height of 30 cm is filled with water and poured into a cylindrical container with the same height as its bottom, what is the distance from the mouth of the container to the surface of the water in cm
一个高30厘米的圆锥容器，盛满水倒入和他等底等高的圆柱体容器，容器口到水面的距离是多少厘米
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">30 * (1/3)</gadget>
<output>10</output>

<gadget id="calculator">30 - 10</gadget>
<output>20</output>

<result>20</result>