A part is drawn on a drawing with a scale of 20:1. The corresponding length on the drawing is 12cm. What is the actual length of this part in cm?
一个零件，画在比例尺是20：1的图纸上，在图纸上的对应长是12cm，这个零件实际长多少cm．
<gadget id="calculator">20 / 1</gadget>
<output>20</output>

<gadget id="calculator">12 / 20</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>