2. Решите уравнения: a) $$\frac{1}{7}x = \frac{32}{21}$$ b) $$\frac{8}{3} : y = \frac{10}{9}$$

Решение: a) $$\frac{1}{7}x = \frac{32}{21}$$ $$x = \frac{32}{21} : \frac{1}{7} = \frac{32}{21} \cdot \frac{7}{1} = \frac{32 \cdot 7}{21 \cdot 1} = \frac{32 \cdot 1}{3 \cdot 1} = \frac{32}{3} = 10 \frac{2}{3}$$ б) $$\frac{8}{3} : y = \frac{10}{9}$$ $$y = \frac{8}{3} : \frac{10}{9} = \frac{8}{3} \cdot \frac{9}{10} = \frac{8 \cdot 9}{3 \cdot 10} = \frac{4 \cdot 3}{1 \cdot 5} = \frac{12}{5} = 2 \frac{2}{5}$$