If A and B work together to complete a job in 6 hours, A alone will take 10 hours to complete it, how many hours will B alone need to complete it?
一件工作，甲、乙合作6小时完成，甲单独做要用10小时完成，乙单独做要用多少小时完成？
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/6) - (1/10)</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">1 / (1/15)</gadget>
<output>15</output>

<result>15</result>