\(\boxed{\mathbf{2.}\mathbf{33}\mathbf{.\ ОК\ ГДЗ - домашка\ на\ }5}\)
\[\textbf{а)}\ \frac{4}{13} + \frac{3}{13} = \frac{4 + 3}{13} = \frac{7}{13}\]
\[\textbf{б)}\ \frac{7}{11} - \frac{1}{11} = \frac{7 - 1}{11} = \frac{6}{11}\]
\[\textbf{в)}\ 4\frac{3}{9} + 2\frac{1}{9} = 6\frac{3 + 1}{9} = 6\frac{4}{9}\]
\[\textbf{г)}\ 8\frac{4}{5} - 7\frac{2}{5} = 1\frac{4 - 2}{5} = 1\frac{2}{5}\]
\[\textbf{д)}\ 3\frac{9}{16} + 2\frac{3}{16} = 5\frac{9 + 3}{16} = 5\frac{12}{16}\]
\[\textbf{е)}\ 5\frac{6}{13} - 3\frac{1}{13} = 2\frac{6 - 1}{13} = 2\frac{5}{13}\]
\[\textbf{ж)}\ \frac{9}{22} \cdot \frac{11}{27} = \frac{9 \cdot 11}{11 \cdot 2 \cdot 9 \cdot 3} = \frac{1}{6}\]
\[\textbf{з)}\ \frac{4}{27}\ :\frac{20}{81} = \frac{4}{27} \cdot \frac{81}{20} =\]
\[= \frac{4 \cdot 27 \cdot 3}{27 \cdot 4 \cdot 5} = \frac{3}{5}\]