Master Wang wants to complete a batch of parts production tasks. The number of parts produced on the first day is 20 more than the total number (1/4), and the number of parts produced on the second day is 30 fewer than the total number (2/5). At this time The ratio of the number of parts produced and not produced is 5:3. How many parts are in this batch?
王师傅要完成一批零件生产任务，第一天生产的零件个数比总数的(1/4)多20人，第二天生产的零件比总数的(2/5)少30个，这时已生产与未生产的零件个数的比是5：3．这批零件多少个？
<gadget id="calculator">30 - 20</gadget>
<output>10</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">5 + 3</gadget>
<output>8</output>

<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">(2/5) - (5/8)</gadget>
<output>-9/40 = around -0.225</output>

<gadget id="calculator">(1/4) + (-9/40)</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">10 / (1/40)</gadget>
<output>400</output>

<result>400</result>