6 cows eat 420 kg of grass for a week, how many kg does each cow eat on average per day?
6头奶牛一个星期吃了420千克的青草，平均每头奶牛每天吃多少千克？
<gadget id="calculator">420 / 6 / 7</gadget>
<output>10</output>

<result>10</result>