1/5 •5/10

To multiply the fractions \( \frac{1}{5} \) and \( \frac{5}{10} \), you multiply the numerators together and the denominators together:

\[ \frac{1 \times 5}{5 \times 10} = \frac{5}{50} \]

Now, simplify \( \frac{5}{50} \):

\[ \frac{5}{50} = \frac{1}{10} \]

So, \( \frac{1}{5} \times \frac{5}{10} = \frac{1}{10} \).