Question

at the library, you find 9 books on a certain topic. the librarian tells you that 55% of the books on this topic have been signed out. how many books does the library have a available on the topic?

Answer 1

Multiply 9 books by 55% by doing

9 x .55 = 4.95

We can't have 4.95 books, though so it rounds down to 4 because you can't just add another .05.