227. Выполните сложение: д) 2 21/26 + (-3 4/13) е) 11/12 + (-7/9) ж) -5/28 + 4 3/12 з) -3 7/12 - 2 5/8

д) (2 \frac{21}{26} + (-3 \frac{4}{13}) = \frac{73}{26} - \frac{43}{13} = \frac{73 - 86}{26} = \frac{-13}{26} = -\frac{1}{2}) е) (\frac{11}{12} + (-\frac{7}{9}) = \frac{11}{12} - \frac{7}{9} = \frac{33 - 28}{36} = \frac{5}{36}) ж) \(-\frac{5}{28} + 4 \frac{3}{12}\) = \(-\frac{5}{28} + \frac{48+3}{12}\) = \(-\frac{5}{28} + \frac{51}{12}\) = \(-\frac{5}{28} + \frac{17}{4}\) = \(\frac{-5+119}{28}\) = \(\frac{114}{28}\) = \(\frac{57}{14}\) = \(4 \frac{1}{14}\) з) \(-3 \frac{7}{12} - 2 \frac{5}{8}\) = \(-\frac{43}{12} - \frac{21}{8}\) = \(\frac{-86-63}{24}\) = \(-\frac{149}{24}\) = \(-6 \frac{5}{24}\)