To add the fractions \( \frac{1}{4} \) and \( \frac{3}{8} \), we need a common denominator. The denominators are 4 and 8, and the least common denominator (LCD) is 8.
Now, we will convert \( \frac{1}{4} \) to have a denominator of 8:
\[ \frac{1}{4} = \frac{1 \times 2}{4 \times 2} = \frac{2}{8} \]
Now we can add \( \frac{2}{8} \) and \( \frac{3}{8} \):
\[ \frac{2}{8} + \frac{3}{8} = \frac{2 + 3}{8} = \frac{5}{8} \]
So,
\[ \frac{1}{4} + \frac{3}{8} = \frac{5}{8} \]