If a factory burns 20 kilograms of coal per day, it can be burned for 50 days. If the factory wants to ensure that the coal is burned for at least 25 days, the amount of coal burned per day cannot exceed how many kilograms.
某工厂库存的煤，若每天烧20千克，可以烧50天，若工厂要保证这些煤至少烧25天，每天烧的煤不能超过多少千克．
<gadget id="calculator">50 / 25</gadget>
<output>2</output>

<gadget id="calculator">20 * 2</gadget>
<output>40</output>

<result>40</result>