25 cows in a dairy farm eat a total of 900 kg of grass in 3 days. According to this calculation, how many kilograms of grass does each cow eat per day on average?
奶牛场25头牛3天一共吃900千克草．照这样计算，平均每头牛每天吃多少千克草？
<gadget id="calculator">900 / 3 / 25</gadget>
<output>12</output>

<result>12</result>