factory produces a batch of parts, 35% of the total is produced in the first week, and 3600 are produced in the second week. At this time, a total of (3/4) more than 400 of the total is produced. How many parts are there in this batch?
某厂生产一批零件，第一周生产了总数的35%，第二周生产了3600个，这时共生产了总数的(3/4)多400个．这批零件共有多少个？
<gadget id="calculator">3_600 - 400</gadget>
<output>3_200</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">35 / 100</gadget>
<output>7/20 = around 0.35</output>

<gadget id="calculator">(3/4) - (7/20)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">3_200 / (2/5)</gadget>
<output>8_000</output>

<result>8_000</result>