$$6\frac{1}{6} = \frac{37}{6}$$
$$\frac{1}{3}\sqrt{45} = \frac{1}{3}\sqrt{9 \cdot 5} = \frac{1}{3} \cdot 3 \sqrt{5} = \sqrt{5}$$
Сравним $$\frac{37}{6}$$ и $$\sqrt{5}$$:
$$\frac{37}{6} \approx 6,17$$
$$\sqrt{5} \approx 2,24$$
$$\frac{37}{6} > \sqrt{5}$$
$$\textbf{Ответ: } 6\frac{1}{6} > \frac{1}{3}\sqrt{45}$$