It seems to me that 2 shelves with 20 books each would work as well as 20s with 2b, 4s with 10b, 10s with 4b, 5s with 8b and 8s with 5b. Is this correct?
Well, if you are trying to fit all of the books in each shelf then it would not work because the number of books should have an even number on each shelf. Like how 2 shelves can fit 20 books. It means that each shelf contains 10 books.
