A cylindrical container, the radius of the bottom surface measured from the inside is 5 cm, and the height is 8 cm. After the container is filled with water, it is poured into a container with a length of 20 cm, a width of 10 cm, and a height of 9 cm. What is the height of the water surface in cm? ?
一个圆柱形容器，从里面量的底面半径5厘米，高8厘米，容器装满水后，再全部倒进一个长20厘米，宽10厘米，高9厘米形容器中，水面的高度是多少厘米？
<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25 * 8</gadget>
<output>628</output>

<gadget id="calculator">20 * 10</gadget>
<output>200</output>

<gadget id="calculator">628 / 200</gadget>
<output>157/50 = around 3.14</output>

<result>157/50 = around 3.14</result>