13. Which one of the following examples represents a proper fraction?

O A. 15/22

O B. 8/8

O C. 12/9

OD. 3/2

The answer is A because it's the only answer where the top number is less then the bottom

15/22 is the only proper fraction because its numerator (the top number) is less than the denominator (the bottom number).

Why the other answers aren't proper:

8/8 may look like a proper fraction, but it isn't. Proper fractions are also supposed to be less than 1, but this fraction is equivalent to 1. Also 12/9 and 3/2 are both improper fractions because their numerators are bigger than their denominators.