9. Выполните действия: 1/6 + 2/3; 8/9 + 1/2 − 1/4; 3 2/10 · 2 2/9; 1/16 : 1/19.

1. \(\frac{1}{6}+\frac{2}{3}=\frac{1}{6}+\frac{4}{6}=\frac{5}{6}\);
2. \(\frac{8}{9}+\frac{1}{2}-\frac{1}{4}=\frac{8}{9}+\frac{1}{4}=\frac{32}{36}+\frac{9}{36}=\frac{41}{36}=1\frac{5}{36}\);
3. \(3\frac{2}{10}\cdot2\frac{2}{9}=\frac{16}{5}\cdot\frac{20}{9}=\frac{64}{9}=7\frac{1}{9}\);
4. \(\frac{1}{16}:\frac{1}{19}=\frac{1}{16}\cdot19=\frac{19}{16}=1\frac{3}{16}\).

Ответ: \(\frac{5}{6};\ 1\frac{5}{36};\ 7\frac{1}{9};\ 1\frac{3}{16}\).