The school bought back 480 books and distributed them to four classes in the third grade on average. Each class has 6 groups. How many books can each group get on average?
学校购回480本图书，平均分给三年级四个班，每个班有6个小组，平均每个小组可以分到多少本书？
<gadget id="calculator">480 / 4 / 6</gadget>
<output>20</output>

<result>20</result>