To add mixed numbers, we first add the whole numbers together and then add the fractions together. In this case, 1 + 2 = 3 for the whole numbers. Then, we add the fractions 1/2 and 1/3 together. To do this, we need to find a common denominator, which is 6. Converting 1/2 to have a denominator of 6 gives us 3/6, and converting 1/3 to have a denominator of 6 gives us 2/6. Adding 3/6 and 2/6 together gives us 5/6. Therefore, the answer is 3 5/6.