№2. Выполните действия: 1) \(\frac{3}{28} + \frac{15}{28} - \frac{11}{28}\); 2) \(3\frac{7}{23} - 1\frac{4}{23} + 5\frac{9}{23}\); 3) \(1-\frac{17}{20}\); 4) \(5\frac{3}{8} - 3\frac{5}{8}\)

1) \(\frac{3}{28} + \frac{15}{28} - \frac{11}{28} = \frac{3 + 15 - 11}{28} = \frac{7}{28} = \frac{1}{4}\)

2) \(3\frac{7}{23} - 1\frac{4}{23} + 5\frac{9}{23} = (3 - 1 + 5) + (\frac{7}{23} - \frac{4}{23} + \frac{9}{23}) = 7 + \frac{7 - 4 + 9}{23} = 7 + \frac{12}{23} = 7\frac{12}{23}\)

3) \(1 - \frac{17}{20} = \frac{20}{20} - \frac{17}{20} = \frac{20 - 17}{20} = \frac{3}{20}\)

4) \(5\frac{3}{8} - 3\frac{5}{8} = 4\frac{11}{8} - 3\frac{5}{8} = (4 - 3) + (\frac{11}{8} - \frac{5}{8}) = 1 + \frac{11 - 5}{8} = 1 + \frac{6}{8} = 1\frac{3}{4}\)