A project can be completed in 12 days by teams A and B working together. Now, team A works alone for 2 days and then B works alone for 1 day to complete the whole project together (3/20). How many days will it take if B alone completes the whole project ?
一项工程甲乙两队合做12天就能完成，现先由甲队单独做2天后乙单独做1天，共同完成全工程的(3/20)，如果由乙单独完成全工程要多少天？
<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">3 / 20</gadget>
<output>3/20 = around 0.15</output>

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

<gadget id="calculator">(3/20) - (1/12)</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/12) - (1/15)</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">1 / (1/60)</gadget>
<output>60</output>

<result>60</result>