23) \( \frac{4 \sqrt{3}}{5 \sqrt{5}} \)

To simplify \( \frac{4 \sqrt{3}}{5 \sqrt{5}} \), we can multiply both the numerator and the denominator by \( \sqrt{5} \) to eliminate the square root in the denominator. This gives us: \[ \frac{4 \sqrt{3} \cdot \sqrt{5}}{5 \sqrt{5} \cdot \sqrt{5}} = \frac{4 \sqrt{15}}{5 \cdot 5} = \frac{4 \sqrt{15}}{25} \] Thus, the simplified form is \( \frac{4 \sqrt{15}}{25} \).