We assume that girls bind X books on average and boys bind 2x books on average. According to "the total number of books bound by girls will definitely exceed 30, and the total number of books bound by boys and girls will definitely be less than 98", the inequality equations can be solved in a list.

Solution: Solution: If girls bind X books on average, boys bind 2x books on average.

The solution is 5 < x < 7.

Because the number of bound magazines should be an integer,

So x=6,

Then 2x = 12.

A: On average, boys bind 12 books and girls bind 6 books.