Master Li processed a batch of parts in two days. The first day processed 20% more parts than the second day, and the second day processed 50 fewer parts than the first day. How many parts are there in total?
李师傅2天加工了一批零件，第一天比第二天多加工了20%，第二天比第一天少加工了50个，这批零件一共有多少个？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">50 / (1/5)</gadget>
<output>250</output>

<gadget id="calculator">250 + 50 + 250</gadget>
<output>550</output>

<result>550</result>