project is completed in 16 days by A alone, and completed by B in 12 days alone. If A works for a certain number of days first, and then B continues to do the rest of the project alone, it takes 14 days to complete the entire project. How many days did A do it first? ?
一件工程，甲单独做16天完成，乙单独做12天完成，若甲先做若干天后，由乙接着单独做余下的工程，完成全部的工程共用了14天，问甲先做了多少天？
<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/12) * 14</gadget>
<output>7/6 = around 1.166667</output>

<gadget id="calculator">(7/6) - 1</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / 16</gadget>
<output>1/16 = around 0.0625</output>

<gadget id="calculator">(1/12) - (1/16)</gadget>
<output>1/48 = around 0.020833</output>

<gadget id="calculator">(1/6) / (1/48)</gadget>
<output>8</output>

<result>8</result>