A square vegetable field has a side length of 40 meters, and its side length is reduced to one thousandth of its original size. What is the perimeter of the reduced figure?
一块正方形菜地边长为40米，把它的边长缩小为原来的一千分之一，缩小后的图形周长是多少？
<gadget id="calculator">1 / 1_000</gadget>
<output>1/1_000 = around 0.001</output>

<gadget id="calculator">40 * (1/1_000)</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">(1/25) * 4</gadget>
<output>4/25 = around 0.16</output>

<result>4/25 = around 0.16</result>