The master and the apprentice work together to process a batch of parts. The master alone takes 100 days to complete, and the apprentice alone takes 150 days to complete. Now the master and apprentice work together for 50 days, how many days will it take for the apprentice to process the remaining parts?
师徒两人合作加工一批零件，师傅单独做需要100天完成，徒弟单独做需要150天完成．现师徒两人合干50天，则徒弟加工剩下的零件还需要多少天？
<gadget id="calculator">1 / 100</gadget>
<output>1/100 = around 0.01</output>

<gadget id="calculator">1 / 150</gadget>
<output>1/150 = around 0.006667</output>

<gadget id="calculator">(1/100) + (1/150)</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">(1/60) * 50</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">1 - (5/6)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/6) / (1/150)</gadget>
<output>25</output>

<result>25</result>