Whenever you are working with fractions, it is a good idea to make sure it is "just" a fraction.
Change all mixed numbers into an improper fraction:
Multiply the denominator to the whole number and add the numerator. 2 1/3 = 7/3
When adding fractions, the denominators must be the same.
You add the numerators, and keep the denominator the same! 3/7 + 2/7 = 5/7
When multiplying fractions, multiply tops to tops and bottoms to bottoms. (3/7)(1/7) = 6/49