For a certain project, A alone needs 12 days to complete, B needs 8 days, A does half of it for B, B does the remaining half and then A completes it, how many days will the whole project take?
某项工程，甲单独完成需要12天，乙需要8天，甲做一半换乙，乙做剩余一半又换甲完成，那么整个工程需花费多少天．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

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

<gadget id="calculator">(1/2) / (1/8)</gadget>
<output>4</output>

<gadget id="calculator">(1/2) * 4</gadget>
<output>2</output>

<gadget id="calculator">(1/2) * (1/2)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

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

<gadget id="calculator">(3/4) / (1/12)</gadget>
<output>9</output>

<gadget id="calculator">2 + 9</gadget>
<output>11</output>

<result>11</result>