1. Выполните действия: a) 16/19 - 11/19 + 4/19; б) 6 5/13 + 2 9/13; в) 5 - 3 6/7; г) 7 2/9 - 3 4/9.

Решение: a) \(\frac{16}{19} - \frac{11}{19} + \frac{4}{19} = \frac{16 - 11 + 4}{19} = \frac{9}{19}\) б) \(6 \frac{5}{13} + 2 \frac{9}{13} = 6 + \frac{5}{13} + 2 + \frac{9}{13} = 8 + \frac{5+9}{13} = 8 + \frac{14}{13} = 8 + 1 \frac{1}{13} = 9 \frac{1}{13}\) в) \(5 - 3 \frac{6}{7} = 4 \frac{7}{7} - 3 \frac{6}{7} = (4 - 3) + (\frac{7}{7} - \frac{6}{7}) = 1 \frac{1}{7}\) г) \(7 \frac{2}{9} - 3 \frac{4}{9} = 6 \frac{11}{9} - 3 \frac{4}{9} = (6 - 3) + (\frac{11}{9} - \frac{4}{9}) = 3 + \frac{7}{9} = 3 \frac{7}{9}\) Ответ: а) \(\frac{9}{19}\); б) \(9 \frac{1}{13}\); в) \(1 \frac{1}{7}\); г) \(3 \frac{7}{9}\)