The apprentice processes 78 parts every day, and the number of parts processed by the master is 15 times less than that of the apprentice. How many parts does the master process every day?
徒弟每天加工78个零件，师傅每天加工的个数比徒弟的3倍少15个，师傅每天加工多少个零件？
<gadget id="calculator">78 * 3</gadget>
<output>234</output>

<gadget id="calculator">234 - 15</gadget>
<output>219</output>

<result>219</result>