a) $$11\frac{2}{7} + 4\frac{3}{7} - 6\frac{4}{7} = (11 + 4 - 6) + (\frac{2}{7} + \frac{3}{7} - \frac{4}{7}) = 9 + \frac{1}{7} = 9\frac{1}{7}$$.
б) $$26\frac{7}{19} - 13\frac{4}{19} + 5\frac{2}{19} = (26 - 13 + 5) + (\frac{7}{19} - \frac{4}{19} + \frac{2}{19}) = 18 + \frac{5}{19} = 18\frac{5}{19}$$.
в) $$44\frac{2}{9} + 8\frac{5}{9} - \frac{7}{9} = (44 + 8) + (\frac{2}{9} + \frac{5}{9} - \frac{7}{9}) = 52 + 0 = 52$$.
г) $$5\frac{7}{10} + 3\frac{9}{10} + 1\frac{3}{10} = (5 + 3 + 1) + (\frac{7}{10} + \frac{9}{10} + \frac{3}{10}) = 9 + \frac{19}{10} = 9 + 1\frac{9}{10} = 10\frac{9}{10}$$.
д) $$3\frac{17}{100} - 2\frac{13}{100} - 1 = (3 - 2 - 1) + (\frac{17}{100} - \frac{13}{100}) = 0 + \frac{4}{100} = \frac{4}{100} = \frac{1}{25}$$.
e) $$8 - 4\frac{31}{100} - 2\frac{57}{100} = (8 - 4 - 2) - (\frac{31}{100} + \frac{57}{100}) = 2 - \frac{88}{100} = 2 - \frac{22}{25} = \frac{50}{25} - \frac{22}{25} = \frac{28}{25} = 1\frac{3}{25}$$.