шите сложение: +(−) 13 B) −1+; 8 д) −1 +; 5 4 ж) −2 +3; + (−1); г) −5 +3; е) − +5; 3) 3 + −4

Выполним сложение чисел: 1) \[\frac{4}{7} + (-\frac{7}{13}) = \frac{4}{7} - \frac{7}{13} = \frac{4 \cdot 13}{7 \cdot 13} - \frac{7 \cdot 7}{13 \cdot 7} = \frac{52}{91} - \frac{49}{91} = \frac{3}{91}\] 2) \[-1 + \frac{3}{8} = -\frac{8}{8} + \frac{3}{8} = \frac{-8 + 3}{8} = -\frac{5}{8}\] 3) \[-1\frac{2}{5} + \frac{3}{4} = -\frac{7}{5} + \frac{3}{4} = -\frac{7 \cdot 4}{5 \cdot 4} + \frac{3 \cdot 5}{4 \cdot 5} = -\frac{28}{20} + \frac{15}{20} = \frac{-28 + 15}{20} = -\frac{13}{20}\] 4) \[-2\frac{1}{3} + 3\frac{2}{5} = -\frac{7}{3} + \frac{17}{5} = -\frac{7 \cdot 5}{3 \cdot 5} + \frac{17 \cdot 3}{5 \cdot 3} = -\frac{35}{15} + \frac{51}{15} = \frac{-35 + 51}{15} = \frac{16}{15} = 1\frac{1}{15}\] 5) \[\frac{4}{5} + (-\frac{11}{6}) = \frac{4}{5} - \frac{11}{6} = \frac{4 \cdot 6}{5 \cdot 6} - \frac{11 \cdot 5}{6 \cdot 5} = \frac{24}{30} - \frac{55}{30} = \frac{24 - 55}{30} = -\frac{31}{30} = -1\frac{1}{30}\] 6) \[-5\frac{5}{8} + 3\frac{1}{4} = -\frac{45}{8} + \frac{13}{4} = -\frac{45}{8} + \frac{13 \cdot 2}{4 \cdot 2} = -\frac{45}{8} + \frac{26}{8} = \frac{-45 + 26}{8} = -\frac{19}{8} = -2\frac{3}{8}\] 7) \[-\frac{4}{5} + 5\frac{4}{15} = -\frac{4}{5} + \frac{79}{15} = -\frac{4 \cdot 3}{5 \cdot 3} + \frac{79}{15} = -\frac{12}{15} + \frac{79}{15} = \frac{-12 + 79}{15} = \frac{67}{15} = 4\frac{7}{15}\] 8) \[3\frac{8}{11} + (-4\frac{3}{22}) = \frac{41}{11} - \frac{91}{22} = \frac{41 \cdot 2}{11 \cdot 2} - \frac{91}{22} = \frac{82}{22} - \frac{91}{22} = \frac{82 - 91}{22} = -\frac{9}{22}\]