845. Выполните действие: 1) 8 + 4/21; 2) 5 6/19 + 3 5/19; 3) 7 7/16 − 3 3/16; 4) 10 12/17 + 5 4/17 − 3 8/17.

1. \(8+\frac{4}{21}=8\frac{4}{21}\).
2. \(5\frac{6}{19}+3\frac{5}{19}=8\frac{11}{19}\).
3. \(7\frac{7}{16}-3\frac{3}{16}=4\frac{4}{16}=4\frac{1}{4}\).
4. \(10\frac{12}{17}+5\frac{4}{17}-3\frac{8}{17}=12\frac{8}{17}\).

Ответ: 1) \(8\frac{4}{21}\); 2) \(8\frac{11}{19}\); 3) \(4\frac{1}{4}\); 4) \(12\frac{8}{17}\).