The auto parts factory has to process 2,440 auto parts. Originally, it processed 80 per day. After working for 20 days, it processed 40 more per day. How many days will it take to process the rest?
汽车配件厂要加工2440个汽车零件，原来每天加工80个，工作20天后，每天多加工40个．剩下的还要加工多少天？
<gadget id="calculator">80 * 20</gadget>
<output>1_600</output>

<gadget id="calculator">2_440 - 1_600</gadget>
<output>840</output>

<gadget id="calculator">80 + 40</gadget>
<output>120</output>

<gadget id="calculator">840 / 120</gadget>
<output>7</output>

<result>7</result>