There are 15 bookshelves in the school library, each book has 5 layers, and each layer can hold 50 books. How many books can these bookshelves hold in total?
学校图书室有15个书架，每个书有5层，每层可放50本书，这些书架一共可放多少本书？
<gadget id="calculator">5 * 15 * 50</gadget>
<output>3_750</output>

<result>3_750</result>