On a drawing with a scale of 50:1, the length of a precision part is measured to be 20 cm. What is the actual length of this part in centimeters?
在比例尺为50：1的图纸上，量得一种精密零件的长为20厘米，这种零件的实际长度是多少厘米．
<gadget id="calculator">50 / 1</gadget>
<output>50</output>

<gadget id="calculator">20 / 50</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>