Guangming Learning Aids Factory needs to produce 20,000 bags of math teaching aids, with an average of 408 bags per day. It has been produced for 45 days. How many bags are left unfinished?
光明学具厂要生产数学教具20000袋，平均每天生产408袋，已经生产了45天，还剩多少袋没有做完呢？
<gadget id="calculator">20_000 - 18_306</gadget>
<output>1_694</output>

<result>1_694</result>