The library buys back a batch of new books, 70 books are placed on each floor, each bookshelf has 4 floors, and a total of 12 such bookshelves are filled. How many new books did the library buy back?
图书馆购回一批新书，每层摆70本书，每个书架有4层，共摆满了12个这样的书架．图书馆共购回了多少本新书？
<gadget id="calculator">4 * 12</gadget>
<output>48</output>

<gadget id="calculator">70 * 48</gadget>
<output>3_360</output>

<result>3_360</result>