Номер 1136 пж очень надо даю 20 б

А,б)

$3 + 8 \frac{5}{12} = 11 \frac{5}{12} \\ 10 \frac{6}{7} - 3 = 7 \frac{6}{7}$

в, г)

$4 \frac{2}{13} + 5 \frac{7}{13} = 4 + 5 + \frac{2 + 7}{13} = 9 \frac{9}{13} \\ 8 \frac{7}{12} - 4 \frac{2}{12} = (8 - 4) + \frac{7 - 2}{12} = 4 \frac{5}{12}$

д, е)

$4 \frac{8}{11} + 5 \frac{7}{11} = 4 + 5 + \frac{8 + 7}{11} = 9 + \frac{15}{11} = 9 + 1 \frac{4}{11} = 10 \frac{4}{11} \\ 7 \frac{5}{9} - 2 \frac{8}{9} = (7 - 2) + \frac{5 - 8}{9} = 5 + ( - \frac{3}{9} ) = 4 \frac{9}{9} - \frac{3}{9} = 4 \frac{9 - 3}{9} = 4 \frac{6}{9} = 4 \frac{2}{3}$

ж, з)

$7 - \frac{3}{8} = 6 \frac{8}{8} - \frac{3}{8} = 6 \frac{8 - 3}{8} = 6 \frac{5}{8} \\ 10 - 3 \frac{7}{15} = 9 \frac{15}{15} - 3 \frac{7}{15} = 6 \frac{15 - 7}{15} = 6 \frac{8}{15}$