To add \( \frac{11}{8} \) and \( \frac{3}{8} \), you can simply add the numerators together since they have the same denominator:
\[ \frac{11}{8} + \frac{3}{8} = \frac{11 + 3}{8} = \frac{14}{8} \]
Now, simplify \( \frac{14}{8} \):
\[ \frac{14}{8} = \frac{7}{4} \]
You can also express \( \frac{7}{4} \) as a mixed number:
\[ \frac{7}{4} = 1 \frac{3}{4} \]
So, \( \frac{11}{8} + \frac{3}{8} = \frac{7}{4} \) or \( 1 \frac{3}{4} \).