The factory processes a batch of parts. It has already processed (3/8) of the total number, and then processed 40 more. At this time, the ratio of the number of processed parts to the remaining number is 4:5. How many parts are there in total in this batch? ?
工厂加工一批零件，已经加工了总数的(3/8)，后来又加工了40个，这时已加工的个数和剩下的个数的比是4：5，这批零件共多少个？
<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">(4/9) - (3/8)</gadget>
<output>5/72 = around 0.069444</output>

<gadget id="calculator">40 / (5/72)</gadget>
<output>576</output>

<result>576</result>