A rope is cut off (2/5), exactly 4 meters are cut off, how many meters is this rope long?
一根绳子截去(2/5)，正好截去了4米，这根绳子长多少米．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">4 / (2/5)</gadget>
<output>10</output>

<result>10</result>