A workshop needs to produce 180 parts. It has been working for 4 days, and the average production is 25 per day. If the remaining 40 parts are produced per day, how many days will it take to complete?
某车间要生产180个零件，已经工作了4天，平均每天生产25个，剩下的如果每天生产40个，还需几天完成？
<gadget id="calculator">25 * 4</gadget>
<output>100</output>

<gadget id="calculator">180 - 100</gadget>
<output>80</output>

<gadget id="calculator">80 / 40</gadget>
<output>2</output>

<result>2</result>