Решение:
1) $$\frac{5}{10} = \frac{1}{2}$$
2) $$\frac{8}{32} = \frac{1}{4}$$
3) $$\frac{14}{63} = \frac{2}{9}$$
4) $$\frac{25}{40} = \frac{5}{8}$$
5) $$\frac{32}{80} = \frac{2}{5}$$
6) $$\frac{56}{72} = \frac{7}{9}$$
7) $$\frac{72}{108} = \frac{2}{3}$$
8) $$\frac{480}{640} = \frac{3}{4}$$