Выполните действия (№ 111–114)

111. а) $(-\frac{16}{17}) + (-\frac{14}{17}) - (+\frac{15}{17}) - \frac{6}{17} = -\frac{16}{17} - \frac{14}{17} - \frac{15}{17} - \frac{6}{17} = \frac{-16-14-15-6}{17} = -\frac{51}{17} = -3$ б) $-(-\frac{10}{13}) + \frac{3}{13} - (+\frac{5}{13}) + (-\frac{8}{13}) = \frac{10}{13} + \frac{3}{13} - \frac{5}{13} - \frac{8}{13} = \frac{10+3-5-8}{13} = \frac{0}{13} = 0$ в) -(+\frac{5}{7}) + (-\frac{6}{7}) - (-\frac{1}{7}) + (+\frac{3}{7}) = -\frac{5}{7} - \frac{6}{7} + \frac{1}{7} + \frac{3}{7} = \frac{-5-6+1+3}{7} = -\frac{7}{7} = -1$ г) $-(-\frac{16}{19}) - \frac{2}{19} + (-\frac{5}{19}) + \frac{10}{19} = \frac{16}{19} - \frac{2}{19} - \frac{5}{19} + \frac{10}{19} = \frac{16-2-5+10}{19} = \frac{19}{19} = 1$ 112. а) $(-\frac{1}{2}) + (-\frac{7}{10}) - (-\frac{3}{5}) - (+\frac{11}{20}) = -\frac{10}{20} - \frac{14}{20} + \frac{12}{20} - \frac{11}{20} = \frac{-10-14+12-11}{20} = -\frac{23}{20} = -1\frac{3}{20} = -1,15$ б) $\frac{17}{30} - (-\frac{5}{6}) + (-\frac{3}{10}) - (+\frac{8}{15}) = \frac{17}{30} + \frac{25}{30} - \frac{9}{30} - \frac{16}{30} = \frac{17+25-9-16}{30} = \frac{17}{30}$ в) -(+\frac{7}{15}) + (+\frac{4}{9}) + (-\frac{28}{45}) - (-\frac{2}{3}) = -\frac{21}{45} + \frac{20}{45} - \frac{28}{45} + \frac{30}{45} = \frac{-21+20-28+30}{45} = \frac{1}{45}$ г) $-(-\frac{1}{2}) - \frac{49}{50} - (+\frac{3}{5}) + (-\frac{9}{10}) = \frac{25}{50} - \frac{49}{50} - \frac{30}{50} - \frac{45}{50} = \frac{25-49-30-45}{50} = -\frac{99}{50} = -1\frac{49}{50} = -1,98$ Ответ: 111: а) -3, б) 0, в) -1, г) 1; 112: а) -1,15, б) 17/30, в) 1/45, г) -1,98.