Сокращение дробей

1. $$rac{7x}{7y} = \frac{x}{y}$$
2. $$\frac{3a}{15b} = \frac{a}{5b}$$
3. $$\frac{xy}{xm} = \frac{y}{m}$$
4. $$\frac{ab}{b^2} = \frac{a}{b}$$
5. $$\frac{5ac}{4ab} = \frac{5c}{4b}$$
6. $$\frac{10xy}{10my} = \frac{x}{m}$$