A rope is 5 meters long, if (2/5) of it is used up, how many meters will be used up?
一根绳子长5米，用去它的(2/5)，用去多少米．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

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

<result>2</result>