The school bought 800 books and placed them on 2 bookshelves. Each shelf has 4 floors. How many books are placed on each floor on average?
学校买来800本书，放在2个书架上，每个书架有4层，平均每层放多少本书？
<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">800 / 8</gadget>
<output>100</output>

<result>100</result>