The school bought 18 bookshelves, each with 5 floors, and each floor can hold 172 books. How many books can these bookshelves hold in total?
学校买来18个书架，每个书架有5层，每层可以放172本书，这些书架一共可以放多少本书？
<gadget id="calculator">172 * 5 * 18</gadget>
<output>15_480</output>

<result>15_480</result>