According to the meaning of the topic: the total number of comics and other scientific books (books) is 501815125 (1), with the most comics and the least other books; (2) (18-12) ÷12, = 6 ÷12, = 50%. A: There are 50% more comic books than science books. (3) 15 ÷. Storybook:15 ÷ 50 = 30%; Science and technology books:12 ÷ 50 = 24%; Other books: 5 ÷ 50 = 10%. As shown in the figure. So the answer is: (1) comics, others; (2)50; (3)3.