Решение примеров на вычитание дробей

a) $$\frac{6}{7} - \frac{2}{3} = \frac{6 \cdot 3}{7 \cdot 3} - \frac{2 \cdot 7}{3 \cdot 7} = \frac{18}{21} - \frac{14}{21} = \frac{18-14}{21} = \frac{4}{21}$$

б) $$\frac{11}{12} - \frac{5}{6} = \frac{11}{12} - \frac{5 \cdot 2}{6 \cdot 2} = \frac{11}{12} - \frac{10}{12} = \frac{11-10}{12} = \frac{1}{12}$$

в) $$\frac{7}{12} - \frac{3}{8} = \frac{7 \cdot 2}{12 \cdot 2} - \frac{3 \cdot 3}{8 \cdot 3} = \frac{14}{24} - \frac{9}{24} = \frac{14-9}{24} = \frac{5}{24}$$

г) $$\frac{9}{14} - \frac{19}{35} = \frac{9 \cdot 5}{14 \cdot 5} - \frac{19 \cdot 2}{35 \cdot 2} = \frac{45}{70} - \frac{38}{70} = \frac{45-38}{70} = \frac{7}{70} = \frac{1}{10}$$