2. Вычислите: a) \(2\frac{1}{2}\cdot 1\frac{1}{5}-2\frac{2}{15}:2\); б) \(4\frac{3}{7}\cdot 8\frac{4}{9}-4\frac{3}{7}\cdot 6\frac{4}{9}.\)

Решение:

1. a) \(2\frac{1}{2}\cdot 1\frac{1}{5}-2\frac{2}{15}:2=\frac{5}{2}\cdot \frac{6}{5}-\frac{32}{15}:2=\frac{5\cdot 6}{2\cdot 5}-\frac{32}{15}\cdot \frac{1}{2}=\frac{1\cdot 3}{1\cdot 1}-\frac{16}{15}=\frac{3}{1}-\frac{16}{15}=\frac{45}{15}-\frac{16}{15}=\frac{29}{15}=1\frac{14}{15}\)
2. б) \(4\frac{3}{7}\cdot 8\frac{4}{9}-4\frac{3}{7}\cdot 6\frac{4}{9}=4\frac{3}{7}\cdot (8\frac{4}{9}-6\frac{4}{9})=4\frac{3}{7}\cdot 2=\frac{31}{7}\cdot 2=\frac{62}{7}=8\frac{6}{7}\)

Ответ: a) \(1\frac{14}{15}\); б) \(8\frac{6}{7}\).