There are two engineering teams, A and B. The work efficiency of team A is twice that of team B. The two teams work together to complete a project in 6 days. If after 2 days of cooperation, team B will do the rest, how many days will it take team B to complete the project?
甲、乙两个工程队，甲队的工作效率是乙队的2倍，两队合做一项工程需要6天完成．如果合做2天后，余下的由乙队去做，乙队完成这项工程共花多少天．
<gadget id="calculator">2 / 6</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<gadget id="calculator">(1/6) / 3</gadget>
<output>1/18 = around 0.055556</output>

<gadget id="calculator">(2/3) / (1/18)</gadget>
<output>12</output>

<result>12</result>