2/3+1/3

To add the fractions \( \frac{2}{3} \) and \( \frac{1}{3} \), you simply add the numerators while keeping the denominator the same:

\[ \frac{2}{3} + \frac{1}{3} = \frac{2 + 1}{3} = \frac{3}{3} \]

Since \( \frac{3}{3} \) simplifies to 1, the final answer is:

\[ 1 \]