22/15. You must find a common denominator when adding and subtracting fractions. The smallest number that both 3 and 15 will go into is 15. Therefore, the common denominator is 15.
You then must multiply 2 by 5, because that is what you had to multiply 3 by to get 15. Then you must multiply 4 by 3 because that is what you had to multiply 5 by to get 15. You now have the fractions 10/15 and 12/15. When adding fractions, the denominator stays the same and you add the numerators. Therefore, the answer is 22/15, which does not reduce.