After cutting a 2-meter-long rope by 0.5 meters, the remaining length is how many times the cut length.
把一根2米长的绳子截下0.5米后，余下的长度是截下的多少倍．
<gadget id="calculator">2 - 0.5</gadget>
<output>1.5</output>

<gadget id="calculator">1.5 / 0.5</gadget>
<output>3</output>

<result>3</result>