Take a cube billet with a side length of 4 meters and forge it into a rectangular steel. It is known that the width of the forged steel is 40 decimeters and the height is 25 decimeters. How many meters is the length?
把一块棱长是4米的正方体钢坯，锻成长方体钢材，已知锻成的钢材的宽是40分米，高是25分米，长是多少米？
<gadget id="calculator">4 * 10 * 25</gadget>
<output>1_000</output>

<gadget id="calculator">10 / 1_000 / 10</gadget>
<output>1/1_000 = around 0.001</output>

<gadget id="calculator">4 * 10 * 4 * 10 * 4 * (1/1_000)</gadget>
<output>32/5 = around 6.4</output>

<result>32/5 = around 6.4</result>