It takes 6 days to process 480 parts by the master alone, and 8 days to do it by the apprentice. Now the master will do it for 2 days first, and then the master and apprentice will work together. How many days will it take to complete the task?
加工480个零件，由师傅单独做，需要6天；由徒弟做，需要8天．现在由师傅先做2天，接着再由师徒两人合做，还要多少天才能完成任务？
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/6) * 2</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 / 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">(2/3) / (7/24)</gadget>
<output>16/7 = around 2.285714</output>

<result>16/7 = around 2.285714</result>