The apprentice processes 120 parts in 8 hours, and the master processes 160 parts in 5 hours. On average, how many parts does the master process more than the apprentice per hour?
徒弟8小时加工120个零件，师傅5小时加工160个零件，师傅平均每小时比徒弟多加工多少个零件？
<gadget id="calculator">160 / 5</gadget>
<output>32</output>

<gadget id="calculator">120 / 8</gadget>
<output>15</output>

<gadget id="calculator">32 - 15</gadget>
<output>17</output>

<result>17</result>