a) $$6 + 8\frac{7}{13} = 6 + \frac{8 \cdot 13 + 7}{13} = 6 + \frac{104 + 7}{13} = 6 + \frac{111}{13} = 6 + 8\frac{7}{13} = 14\frac{7}{13}$$
Ответ: $$14\frac{7}{13}$$
б) $$12 + 19\frac{5}{24} = 31\frac{5}{24}$$
Ответ: $$31\frac{5}{24}$$
в) $$5\frac{7}{15} + 8\frac{4}{15} = (5+8) + (\frac{7}{15} + \frac{4}{15}) = 13 + \frac{11}{15} = 13\frac{11}{15}$$
Ответ: $$13\frac{11}{15}$$
г) $$13\frac{5}{101} + 7\frac{25}{101} = (13 + 7) + (\frac{5}{101} + \frac{25}{101}) = 20 + \frac{30}{101} = 20\frac{30}{101}$$
Ответ: $$20\frac{30}{101}$$
д) $$4\frac{3}{7} + 15\frac{4}{7} = (4+15) + (\frac{3}{7} + \frac{4}{7}) = 19 + \frac{7}{7} = 19 + 1 = 20$$
Ответ: $$20$$
e) $$3\frac{9}{13} + 4\frac{8}{13} = (3+4) + (\frac{9}{13} + \frac{8}{13}) = 7 + \frac{17}{13} = 7 + 1\frac{4}{13} = 8\frac{4}{13}$$
Ответ: $$8\frac{4}{13}$$