2) а) \(\frac{4}{9}\cdot\frac{3}{8}\); б) \(2\frac{6}{7}:1\frac{3}{7}\); в) \(\frac{5}{8}:\frac{9}{10}\); г) \(6\frac{3}{5}\cdot10\).

1. а) \(\frac{4}{9}\cdot\frac{3}{8}=\frac{4\cdot3}{9\cdot8}=\frac{1}{6}\).
2. б) \(2\frac{6}{7}:1\frac{3}{7}=\frac{20}{7}:\frac{10}{7}=\frac{20}{7}\cdot\frac{7}{10}=2\).
3. в) \(\frac{5}{8}:\frac{9}{10}=\frac{5}{8}\cdot\frac{10}{9}=\frac{25}{36}\).
4. г) \(6\frac{3}{5}\cdot10=\frac{33}{5}\cdot10=66\).

Ответ: а) \(\frac{1}{6}\); б) \(2\); в) \(\frac{25}{36}\); г) \(66\).