A batch of parts is divided equally between the master and the apprentice for processing. The ratio of the number of parts processed per hour between the master and the apprentice is 7:5. When the master completes the task, there are still 24 apprentices who have not completed it. How many parts are there in total?
一批零件，平均分给师徒两人加工．师傅和徒弟每小时加工零件个数的比是7：5．当师傅完成任务时，徒弟还有24个没有完成．这批零件一共有多少个？
<gadget id="calculator">7 + 5</gadget>
<output>12</output>

<gadget id="calculator">7 / 12</gadget>
<output>7/12 = around 0.583333</output>

<gadget id="calculator">5 / 12</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">(7/12) - (5/12)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">24 / (1/6)</gadget>
<output>144</output>

<result>144</result>