The bookstore purchased 350 story books. If how many are required, how many literature and art books are purchased, and what conditions can be added? Write down the condition first, and then answer it.
书店购入350本故事书．如果要求多少，购入的文艺书有多少本，可以补充怎件的条件？先把这个条件写下来，再解答．
<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<result>5/7 = around 0.714286</result>