\[\boxed{Страница\ 20.}\]
\[\boxed{\mathbf{1.}}\]
\[1.\]
\[3\frac{4}{5} = \frac{3 \cdot 5 + 4}{5} = \frac{19}{5}.\]
\[2.\]
\[5\frac{2}{3} = \frac{3 \cdot 5 + 2}{3} = \frac{17}{3}\]
\[2\frac{8}{9} = \frac{9 \cdot 2 + 8}{9} = \frac{26}{9}\]
\[4\frac{1}{6} = \frac{6 \cdot 4 + 1}{6} = \frac{25}{6}\]
\[3\frac{5}{17} = \frac{17 \cdot 3 + 5}{17} = \frac{56}{17}\]
\[3.\]
\[\textbf{а)}\ n\ :40 \cdot 100\ (яблонь) - в\ саду.\]
\[\textbf{б)}\ d\ :3 \cdot 14\ (лет) - матери.\]
\[\textbf{в)}\ \ a\ :8 = \frac{a}{8}\ (часть) - всех\ букв\ \]
\[слова\ составляют\ согласные.\]
\[\boxed{\mathbf{2.}}\]
\[1.\]
\[5\frac{1}{3} = \frac{3 \cdot 5 + 1}{3} = \frac{16}{3}.\]
\[2.\]
\[3\frac{1}{8} = \frac{8 \cdot 3 + 1}{8} = \frac{25}{8}\]
\[4\frac{2}{7} = \frac{7 \cdot 4 + 2}{7} = \frac{30}{7}\]
\[6\frac{3}{9} = \frac{9 \cdot 6 + 3}{9} = \frac{57}{9}\]
\[2\frac{8}{35} = \frac{35 \cdot 2 + 8}{35} = \frac{78}{35}\]
\[3.\]
\[\textbf{а)}\ a\ :100 \cdot 95\ (цветов) - дали\ \]
\[всходы.\]
\[\textbf{б)}\ x\ :5 \cdot 9\ (км) - длина\ всей\ \]
\[дороги.\]
\[\textbf{в)}\ 10\ :m = \frac{10}{m}\ (часть) -\]
\[аквариума\ заполнена.\]