A cuboid tank with a length of 50 cm, a width of 40 cm, and a height of 30 cm has a water depth of 20 cm. If a cube with a side length of 10 cm is placed, how many centimeters will the water level in the tank rise?
一个长50厘米、宽40厘米、高30厘米的长方体水箱，水深20厘米．如果放入一块棱长10厘米的正方体石块，那么水箱里的水面将上升多少厘米？
<gadget id="calculator">50 * 40</gadget>
<output>2_000</output>

<gadget id="calculator">10 / 2_000</gadget>
<output>1/200 = around 0.005</output>

<gadget id="calculator">10 * 10 * (1/200)</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>