2 1. Выполни действия: a) 3\frac{6}{9} + 1\frac{7}{9} = б) 5\frac{4}{13} - 3\frac{12}{13} = в) 0 + 8\frac{2}{3} = г) 6\frac{3}{45} - 6\frac{3}{45} = д) 2\frac{3}{5} + \frac{2}{8} + 1\frac{6}{8} + 4\frac{2}{5} = e) (6\frac{4}{10} + 2\frac{5}{7}) - 5\frac{4}{10} =

а) 3\frac{6}{9} + 1\frac{7}{9} = (3+1) + (\frac{6}{9} + \frac{7}{9}) = 4 + \frac{13}{9} = 4 + 1\frac{4}{9} = 5\frac{4}{9}

б) 5\frac{4}{13} - 3\frac{12}{13} = 4\frac{17}{13} - 3\frac{12}{13} = (4 - 3) + (\frac{17}{13} - \frac{12}{13}) = 1 + \frac{5}{13} = 1\frac{5}{13}

в) 0 + 8\frac{2}{3} = 8\frac{2}{3}

г) 6\frac{3}{45} - 6\frac{3}{45} = (6-6) + (\frac{3}{45} - \frac{3}{45}) = 0

д) 2\frac{3}{5} + \frac{2}{8} + 1\frac{6}{8} + 4\frac{2}{5} = (2\frac{3}{5} + 4\frac{2}{5}) + (\frac{2}{8} + 1\frac{6}{8}) = (2+4) + (\frac{3}{5} + \frac{2}{5}) + 1 + (\frac{2}{8} + \frac{6}{8}) = 6 + \frac{5}{5} + 1 + \frac{8}{8} = 6 + 1 + 1 + 1 = 9

e) (6\frac{4}{10} + 2\frac{5}{7}) - 5\frac{4}{10} = (6\frac{4}{10} - 5\frac{4}{10}) + 2\frac{5}{7} = (6-5) + (\frac{4}{10} - \frac{4}{10}) + 2\frac{5}{7} = 1 + 0 + 2\frac{5}{7} = 3\frac{5}{7}