The library bought back a batch of books. Each shelf can hold 150 books. There are 11 bookshelves, but there are still 630 books not put in. How many books did the school buy back in total?
图书室买回一批图书，每个书架可放150本书，放了11个书架，还有630本没放进去，学校一共买回多少本书？
<gadget id="calculator">150 * 11</gadget>
<output>1_650</output>

<gadget id="calculator">1_650 + 630</gadget>
<output>2_280</output>

<result>2_280</result>