The school bought 7 bookshelves, each with 4 floors, and 24 books on each floor. How many books can be placed in total?
学校买回7个书架，每个书架4层，每层放24本书，一共可以放多少本书？
<gadget id="calculator">24 * 4 * 7</gadget>
<output>672</output>

<result>672</result>