Li Qiang rides a bicycle to and from A and B. It takes 6 hours to go there, but the speed increases (1/11) when he comes back, which is how many hours less than when he went there.
李强骑自行车往返甲乙两地，去时用6小时，回来时速度提高了(1/11)，比去时少用了多少小时．
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / 11</gadget>
<output>1/11 = around 0.090909</output>

<gadget id="calculator">1 + (1/11)</gadget>
<output>12/11 = around 1.090909</output>

<gadget id="calculator">(1/6) * (12/11)</gadget>
<output>2/11 = around 0.181818</output>

<gadget id="calculator">1 / (2/11)</gadget>
<output>11/2 = around 5.5</output>

<gadget id="calculator">6 - (11/2)</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>