project can be completed by A alone in 6 days and by B alone in 8 days. After A and B cooperated for 2 days, the workload increased by the remaining 2 times. How many days will it take for A and B to complete the cooperation?
一项工程，甲单独做用6天完成，乙单独做用8天完成．甲、乙合作2天后，工作量增加了剩下的2倍，甲、乙合作还需要几天完成？
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">(1/6) + (1/8)</gadget>
<output>7/24 = around 0.291667</output>

<gadget id="calculator">(7/24) * 2</gadget>
<output>7/12 = around 0.583333</output>

<gadget id="calculator">1 - (7/12)</gadget>
<output>5/12 = around 0.416667</output>

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

<gadget id="calculator">3 / (7/24)</gadget>
<output>72/7 = around 10.285714</output>

<gadget id="calculator">(5/12) * (72/7)</gadget>
<output>30/7 = around 4.285714</output>

<result>30/7 = around 4.285714</result>