A project alone takes 12 days and B alone takes 15 days. After the two teams cooperate for 2 days, how many days will it take for A to do the rest alone?
一项工程，甲单独做需要12天，乙单独做需要15天．两队合作2天后，剩下的由甲独做，还需多少天．
<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/12) + (1/15)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">(3/20) * 2</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">(7/10) / (1/12)</gadget>
<output>42/5 = around 8.4</output>

<result>42/5 = around 8.4</result>