§ Задание 122
\[\boxed{\mathbf{4.}\mathbf{122}}\]
\[\frac{8}{11}\ :5,7 = x\ :17,1\]
\[5,7x = 17,1 \cdot \frac{8}{11}\]
\[x = \frac{17,1 \cdot 8}{5,7 \cdot 11} = \frac{3 \cdot 8}{11} = \frac{24}{11}\]
\[x = 2\frac{2}{11}.\]
\[\boxed{\mathbf{4.}\mathbf{122}}\]
\[\frac{8}{11}\ :5,7 = x\ :17,1\]
\[5,7x = 17,1 \cdot \frac{8}{11}\]
\[x = \frac{17,1 \cdot 8}{5,7 \cdot 11} = \frac{3 \cdot 8}{11} = \frac{24}{11}\]
\[x = 2\frac{2}{11}.\]