[tex]3) \\ \\ a) \\ \\ \frac{2}{3} + \frac{5}{6} + ( - \frac{10}{12}) = \frac{2}{3} + \frac{5}{6} + ( - \frac{5}{6}) = \frac{4}{6} = \frac{2}{3} \\ \\ b) \\ \\ - \frac{5}{7} + ( - \frac{1}{3}) + \frac{5}{7} = - ( \frac{1}{3}) = \frac{ - 1}{3} = - \frac{1}{3} \\ \\ c) \\ \\ \frac{12}{6} + \frac{5}{6} + ( - \frac{10}{5}) = 2 + \frac{5}{6} + ( - 2) = \frac{5}{6} \\ \\ d) \\ \\ - \frac{3}{4} + \frac{7}{2} + \frac{1}{4} = \frac{12}{4} = 3 \\ \\ e) \\ \\ \frac{1}{7} + ( - \frac{4}{3}) + \frac{6}{7} + \frac{1}{3} = \frac{0}{21} = 0 \\ \\ 4) \\ \\ a) \\ \\ \frac{2}{3} + \frac{5}{2} = \frac{19}{6} = 3 \frac{1}{6} \\ \\ b) \\ \\ - \frac{2}{3} + ( - \frac{5}{2}) = - \frac{19}{6} = - 3 \frac{1}{6} \\ \\ c) \\ \\ \frac{2}{3} - \frac{5}{2} = - \frac{11}{6} = - 1 \frac{5}{6} \\ \\ d) \\ \\ - \frac{2}{3} + \frac{5}{2} = \frac{11}{6} = 1 \frac{5}{6} [/tex]
