Process a batch of parts, complete (2/5) on the first day, complete 37.5% on the second day, and there are 90 remaining. How many parts are there in this batch?
加工一批零件，第一天完成(2/5)，第二天完成37.5%，还余下90个，这批零件共有多少个？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">37.5 / 100</gadget>
<output>0.375</output>

<gadget id="calculator">1 - (2/5) - 0.375</gadget>
<output>0.225</output>

<gadget id="calculator">90 / 0.225</gadget>
<output>400</output>

<result>400</result>