On the 10:1 drawing, the length of a part is 4cm, what is the actual length of this part in cm?
在10：1的图纸上，一个零件的长为4cm，这个零件的长实际为多少cm．
<gadget id="calculator">10 / 1</gadget>
<output>10</output>

<gadget id="calculator">4 / 10</gadget>
<output>2/5 = around 0.4</output>

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