The master and apprentice processed 532 parts. After 2.5 hours of processing, there were still 232 parts left unprocessed. The apprentice processed 57 parts per hour. How many parts per hour did the master process?
师徒两人加工532个零件，加工2.5个小时后还剩232个零件没有加工，徒弟每小时加工57个，师傅每小时加工多少个？
<gadget id="calculator">532 - 232</gadget>
<output>300</output>

<gadget id="calculator">300 / 2.5</gadget>
<output>120</output>

<gadget id="calculator">120 - 57</gadget>
<output>63</output>

<result>63</result>