Найдите разность: а) 7 3/5 − 1 2/5; б) 28 6/13 − 7 1/13; в) 6 − 2/5; г) 21 − 5/9; д) 4 1/7 − 1 4/7; е) 12 2/5 − 1 4/5; ж) 4 1/2 − 3 1/4; з) 5 1/7 − 3 20/21.

1. \(7\frac{3}{5}-1\frac{2}{5}=6\frac{1}{5}\).
2. \(28\frac{6}{13}-7\frac{1}{13}=21\frac{5}{13}\).
3. \(6-\frac{2}{5}=5\frac{3}{5}\).
4. \(21-\frac{5}{9}=20\frac{4}{9}\).
5. \(4\frac{1}{7}-1\frac{4}{7}=3-\frac{3}{7}=2\frac{4}{7}\).
6. \(12\frac{2}{5}-1\frac{4}{5}=11-\frac{2}{5}=10\frac{3}{5}\).
7. \(4\frac{1}{2}-3\frac{1}{4}=1+\frac{2}{4}-\frac{1}{4}=1\frac{1}{4}\).
8. \(5\frac{1}{7}-3\frac{20}{21}=5\frac{3}{21}-3\frac{20}{21}=1-\frac{17}{21}=\frac{4}{21}\).

Ответ: а) \(6\frac{1}{5}\); б) \(21\frac{5}{13}\); в) \(5\frac{3}{5}\); г) \(20\frac{4}{9}\); д) \(2\frac{4}{7}\); е) \(10\frac{3}{5}\); ж) \(1\frac{1}{4}\); з) \(\frac{4}{21}\).