A rope is (11/12) meters long, if (3/12) meters are used up, how much more meters are left over than used up
一根绳子长(11/12)米，用去(3/12)米，剩下的比用去的多多少米
<gadget id="calculator">11 / 12</gadget>
<output>11/12 = around 0.916667</output>

<gadget id="calculator">3 / 12</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(11/12) - (1/4) - (1/4)</gadget>
<output>5/12 = around 0.416667</output>

<result>5/12 = around 0.416667</result>