Вычислить: 2 1/2 · 6/7; 3 3/5 · 5/8; 1 1/9 · 9/10; 5 6/7 · 5/12.

1. \(2\frac{1}{2}\cdot\frac{6}{7}=\frac{5}{2}\cdot\frac{6}{7}=\frac{15}{7}=2\frac{1}{7}\).
2. \(3\frac{3}{5}\cdot\frac{5}{8}=\frac{18}{5}\cdot\frac{5}{8}=\frac{18}{8}=\frac{9}{4}=2\frac{1}{4}\).
3. \(1\frac{1}{9}\cdot\frac{9}{10}=\frac{10}{9}\cdot\frac{9}{10}=1\).
4. \(5\frac{6}{7}\cdot\frac{5}{12}=\frac{41}{7}\cdot\frac{5}{12}=\frac{205}{84}=2\frac{37}{84}\).

Ответ: 2\(\frac{1}{7}\); 2\(\frac{1}{4}\); 1; 2\(\frac{37}{84}\).