Выполни действие: a) $5\frac{1}{7} + 1\frac{1}{7}$; б) $1\frac{1}{3} + 3\frac{2}{7}$; в) $3\frac{5}{6} + 6\frac{5}{5}$; г) $8\frac{2}{5} - 9\frac{8}{9}$; д) $5\frac{1}{12} + 1\frac{6}{6}$; е) $5\frac{3}{15} - 3\frac{4}{15}$; ж) $\frac{19}{21} - \frac{11}{15}$; и) $\frac{11}{21} + \frac{2}{26}$; к) $\frac{5}{24} - \frac{7}{60}$

a) $5\frac{1}{7} + 1\frac{1}{7} = 6\frac{2}{7}$ б) $1\frac{1}{3} + 3\frac{2}{7} = \frac{4}{3} + \frac{23}{7} = \frac{28}{21} + \frac{69}{21} = \frac{97}{21} = 4\frac{13}{21}$ в) $3\frac{5}{6} + 6\frac{5}{5} = 3\frac{5}{6} + 7 = 10\frac{5}{6}$ г) $8\frac{2}{5} - 9\frac{8}{9} = \frac{42}{5} - \frac{89}{9} = \frac{378}{45} - \frac{445}{45} = -\frac{67}{45} = -1\frac{22}{45}$. Проверка: $-1\frac{22}{45} + 8\frac{2}{5} = -\frac{67}{45} + \frac{42}{5} = \frac{-67 + 378}{45} = \frac{311}{45} = 6\frac{41}{45} \ne 9\frac{8}{9}$ д) $5\frac{1}{12} + 1\frac{6}{6} = 5\frac{1}{12} + 2 = 7\frac{1}{12}$ е) $5\frac{3}{15} - 3\frac{4}{15} = 2\frac{-1}{15} = 1\frac{14}{15}$. Проверка: $1\frac{14}{15} + 3\frac{4}{15} = 4\frac{18}{15} = 5\frac{3}{15}$ ж) $\frac{19}{21} - \frac{11}{15} = \frac{95}{105} - \frac{77}{105} = \frac{18}{105} = \frac{6}{35}$ и) $\frac{11}{21} + \frac{2}{26} = \frac{11}{21} + \frac{1}{13} = \frac{143 + 21}{273} = \frac{164}{273}$ к) $\frac{5}{24} - \frac{7}{60} = \frac{25}{120} - \frac{14}{120} = \frac{11}{120}$