\[\boxed{\text{170\ (170).\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[\textbf{б)}\ \frac{3}{\frac{1^{\backslash 4}}{2} + \frac{1^{\backslash 2}}{4} + \frac{1}{8}} = \frac{3}{\frac{4 + 2 + 1}{8}} =\]
\[= \frac{3 \cdot 8}{7} = \frac{24}{7} = 3\frac{3}{7}\]