A square steel billet with a side length of 20 decimeters is forged into a rectangular parallelepiped steel with a height and a width of 4 centimeters. What is the length of the forged cuboid steel?
把一块棱长是20分米的正方体钢坯，锻造成高和宽都是4厘米的长方体钢材．锻造成的长方体钢材的长是多少米？
<gadget id="calculator">4 / 10</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) * (2/5)</gadget>
<output>4/25 = around 0.16</output>

<gadget id="calculator">20 / (4/25) / 10</gadget>
<output>25/2 = around 12.5</output>

<gadget id="calculator">20 * 20 * (25/2)</gadget>
<output>5_000</output>

<result>5_000</result>