A rope is (5/6) meters long, and (1/5) meters are used up, how many meters are left?
一根绳子长(5/6)米，用去了(1/5)米，还剩多少米．
<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(5/6) - (1/5)</gadget>
<output>19/30 = around 0.633333</output>

<result>19/30 = around 0.633333</result>