There is a piece of iron with a side length of 20cm. Now it is melted and cast into a cuboid with a cross-sectional area of 40cm**2. What is the length of this cuboid in centimeters?
有一块棱长是20cm的正方体的铁块，现在要把它溶铸成一个横截面积是40cm**2长方体，这个长方体的长是多少厘米？
<gadget id="calculator">20 / 40</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">20 * 20 * (1/2)</gadget>
<output>200</output>

<result>200</result>