\[\boxed{\text{П.16.}}\]
\[\textbf{а)}\ \frac{1}{2} = \frac{4}{8};\ \ \ \ \frac{3}{4} = \frac{6}{8};\ \ \ 1\frac{1}{2} = 1\frac{4}{8};\ \ \ \ \]
\[\frac{7}{8};\ \ \ \ \frac{3}{8}.\]
\[\ \frac{3}{8} < \frac{4}{8} < \frac{6}{8} < \frac{7}{8} < 1\frac{4}{8}\text{.\ }\]
\[В\ порядке\ возрастания:\ \]
\[\frac{3}{8} < \frac{1}{2} < \frac{3}{4} < \frac{7}{8} < 1\frac{1}{2}\text{.\ }\]
\[\textbf{б)}\ \frac{1}{3} = \frac{4}{12};\ \ \ \ 1\frac{2}{3} = 1\frac{8}{12};\ \ \ \ \]
\[\frac{5}{6} = \frac{10}{12};\ \ \ \ \ \frac{2}{3} = \frac{8}{12};\ \ \ \ \frac{7}{12}.\]
\[\frac{4}{12} < \frac{7}{12} < \frac{8}{12} < \frac{10}{12} < 1\frac{8}{12}.\]
\[В\ порядке\ возрастания:\ \]
\[\frac{1}{3} < \frac{7}{12} < \frac{2}{3} < \frac{5}{6} < 1\frac{2}{3}\text{.\ \ \ \ }\]