Упражнение 3. Вычисли: 7 12/13 − (4 + 2 3/5); 10 14/25 − (8 + 1/5); 7 − (4 2/17 − 2 3/34).

1. \(7\frac{12}{13}-(4+2\frac{3}{5})=7\frac{12}{13}-6\frac{3}{5}=\frac{103}{13}-\frac{33}{5}=\frac{515-429}{65}=\frac{86}{65}=1\frac{21}{65}\).

2. \(10\frac{14}{25}-(8+\frac{1}{5})=10\frac{14}{25}-8\frac{1}{5}=\frac{264}{25}-\frac{205}{25}=\frac{59}{25}=2\frac{9}{25}\).

3. \(7-(4\frac{2}{17}-2\frac{3}{34})=7-(4\frac{4}{34}-2\frac{3}{34})=7-2\frac{1}{34}=4\frac{33}{34}\).

Ответ: 1 21/65; 2 9/25; 4 33/34.