1. Выполните деление: 1) 5/7 : 4/5; 2) 6/35 : 18/49; 3) 27/28 : 9/56; 4) 28/45 : 63/40.

1. \(\frac{5}{7}:\frac{4}{5}=\frac{5}{7}\cdot\frac{5}{4}=\frac{25}{28}\).
2. \(\frac{6}{35}:\frac{18}{49}=\frac{6}{35}\cdot\frac{49}{18}=\frac{7}{15}\).
3. \(\frac{27}{28}:\frac{9}{56}=\frac{27}{28}\cdot\frac{56}{9}=6\).
4. \(\frac{28}{45}:\frac{63}{40}=\frac{28}{45}\cdot\frac{40}{63}=\frac{32}{81}\).

Ответ: 1) \(\frac{25}{28}\); 2) \(\frac{7}{15}\); 3) 6; 4) \(\frac{32}{81}\).