First, you need to make the fractions have the same denominator:
15 1/2 ---> 15 + (1/2 x 5) = 15 5/10
2 1/10 ---> 2 1/10
Then you need to subtract them from each other:
15 5/10
- 2 1/10 (or) 15 5/10 - 2 1/10 = 13 4/10
13 4/10
This gets the answer: 13 4/10
