The library has a total of 960 literary books and story books, and the number of literary books is three times that of story books. How many story books have you bought?
图书馆有文艺书和故事书共960本，其中文艺书的本数是故事书的3倍，买来故事书多少本？
<gadget id="calculator">1 + 3</gadget>
<output>4</output>

<gadget id="calculator">960 / 4</gadget>
<output>240</output>

<result>240</result>