39. Сократите: а) \(\frac{6\cdot25}{35\cdot8}\); б) \(\frac{2\cdot9\cdot12}{6\cdot8\cdot3}\); в) \(\frac{9\cdot5+9\cdot3}{2\cdot81}\).

1. а) \(\frac{6\cdot25}{35\cdot8}=\frac{150}{280}=\frac{15}{28}\).
2. б) \(\frac{2\cdot9\cdot12}{6\cdot8\cdot3}=\frac{216}{144}=\frac{3}{2}\).
3. в) \(\frac{9\cdot5+9\cdot3}{2\cdot81}=\frac{9(5+3)}{162}=\frac{72}{162}=\frac{4}{9}\).

Ответ: а) \(\frac{15}{28}\); б) \(\frac{3}{2}\); в) \(\frac{4}{9}\).