For a job, team A does it alone for 10 days, and completes half of it. The rest is completed by teams A and B in 6 days. If this job is done by team B alone, how many days will it take?
一件工作，甲队先单独做了10天，正好完成一半，余下的由甲、乙两队合做6天完成，如果这件工作由乙队单独做要多少天？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) / 6</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/2) / 10</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(1/12) - (1/20)</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">1 / (1/30)</gadget>
<output>30</output>

<result>30</result>