The school library bought back 60 science and technology books and 90 literature and art books. The number of story books bought back is 6 times that of science and technology books. How many books did the school buy back in total?
学校图书室买回科技书60本，文艺书90本．买回的故事书是科技书6倍，学校一共买回多少本书？
<gadget id="calculator">60 * 6</gadget>
<output>360</output>

<gadget id="calculator">360 + 60 + 90</gadget>
<output>510</output>

<result>510</result>