Answer :
number of books = 42 / 5/8 (Note 3 1/2 feet = 42 ins.)
= 42 * 8/5 = 336 / 5 = 67.2
67 books will fit on the shelf.
= 42 * 8/5 = 336 / 5 = 67.2
67 books will fit on the shelf.