Вычислите: 1) 17 : 43; 2) 2/9 : 9; 3) 1/6 : 2/5; 4) 21 : 3/7; 5) 4 2/3 : 3 8/9.

1. \(17:43=\frac{17}{43}\).
2. \(\frac{2}{9}:9=\frac{2}{9}\cdot\frac{1}{9}=\frac{2}{81}\).
3. \(\frac{1}{6}:\frac{2}{5}=\frac{1}{6}\cdot\frac{5}{2}=\frac{5}{12}\).
4. \(21:\frac{3}{7}=21\cdot\frac{7}{3}=49\).
5. \(4\frac{2}{3}:3\frac{8}{9}=\frac{14}{3}:\frac{35}{9}=\frac{14}{3}\cdot\frac{9}{35}=\frac{6}{5}=1\frac{1}{5}\).

Ответ: 1) \(\frac{17}{43}\); 2) \(\frac{2}{81}\); 3) \(\frac{5}{12}\); 4) \(49\); 5) \(1\frac{1}{5}\).