A piece of iron wire is 3 meters long, cut off (1/5) meter, how much is left?
一段铁丝长3米，截去(1/5)米，还剩下多少．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">3 - (1/5)</gadget>
<output>14/5 = around 2.8</output>

<result>14/5 = around 2.8</result>