Решение:
\[ \sqrt{\frac{1}{16} \cdot x^6 \cdot y^4} = \sqrt{\frac{1}{16}} \cdot \sqrt{x^6} \cdot \sqrt{y^4} \]
\[ = \frac{1}{4} \cdot x^{6/2} \cdot y^{4/2} = \frac{1}{4} x^3 y^2 \]
\[ = \frac{1}{4} \cdot 2^3 \cdot 5^2 = \frac{1}{4} \cdot 8 \cdot 25 \]
\[ = \frac{1 \cdot 8 \cdot 25}{4} = \frac{200}{4} = 50 \]
Ответ: 50