Each class borrows books from the school library, among which 12 classes borrow 45 books per class, and 4 classes borrow 48 books per class. How many books have been borrowed from the library?
各班向学校图书室借书，其中12个班每班借45本，4个班每班借48本．图书室一共借出了多少本书？
<gadget id="calculator">45 * 12</gadget>
<output>540</output>

<gadget id="calculator">48 * 4</gadget>
<output>192</output>

<gadget id="calculator">540 + 192</gadget>
<output>732</output>

<result>732</result>