The library purchases science and technology books, literature and art books and life books at a ratio of 5:2:2. A total of 450 books were purchased last month. How many books are there in total for art books and life books?
图书馆按5：2：2购进科技书、文艺书和生活类书．上个月共购进图书450本，期中文艺书和生活类书一共有多少本．
<gadget id="calculator">2 + 2</gadget>
<output>4</output>

<gadget id="calculator">5 + 2 + 2</gadget>
<output>9</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">450 * (4/9)</gadget>
<output>200</output>

<result>200</result>