If A and B work together to complete a project in 6 days, and it takes 10 days for A to complete it alone, how many days will it take for B to complete the project alone?
一项工程，甲、乙两人合作需要6天完成，甲队单独做需要10天才能完成，则乙队单独做需要多少天才能完成这项工程．
<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>