1) $$1 : \frac{4}{7} = \frac{7}{7} : \frac{4}{7} = 7:4$$
2) $$\frac{1}{6} : \frac{3}{4} = \frac{1*4}{6*4} : \frac{3*6}{4*6} = \frac{4}{24} : \frac{18}{24} = 4:18 = 2:9$$
Ответ:
1) 7:4
2) 2:9