To solve the problem \( \frac{4}{5} \div \frac{1}{3} \), you can multiply by the reciprocal of the second fraction.
So, \[ \frac{4}{5} \div \frac{1}{3} = \frac{4}{5} \times \frac{3}{1} = \frac{4 \times 3}{5 \times 1} = \frac{12}{5}. \]
Now, to convert \( \frac{12}{5} \) into a mixed number, divide 12 by 5, which gives you 2 with a remainder of 2. So, you can express it as:
\[ 2 \frac{2}{5}. \]
Thus, the answer is \( 2 \frac{2}{5} \).