It takes 8 days for A and B to finish binding a batch of math books together, and it takes 14 days for A to do it alone. If B does it alone, how many days can it be completed?
甲、乙两人共同完成装订一批数学簿的任务需要8天，甲单独做需要14天，若由乙单独做，几天可以完成？
<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">1 / 14</gadget>
<output>1/14 = around 0.071429</output>

<gadget id="calculator">(1/8) - (1/14)</gadget>
<output>3/56 = around 0.053571</output>

<gadget id="calculator">1 / (3/56)</gadget>
<output>56/3 = around 18.666667</output>

<result>56/3 = around 18.666667</result>