ж) $$(15\frac{1}{2} - 2\frac{3}{8}) - (5\frac{5}{6} + 6\frac{3}{4}) + (10\frac{2}{3} - 5\frac{5}{8}) = (15\frac{4}{8} - 2\frac{3}{8}) - (5\frac{10}{12} + 6\frac{9}{12}) + (10\frac{16}{24} - 5\frac{15}{24}) = 13\frac{1}{8} - 12\frac{19}{12} + 5\frac{1}{24} = 13\frac{3}{24} - 13\frac{7}{12} + 5\frac{1}{24} = 13\frac{3}{24} - 13\frac{14}{24} + 5\frac{1}{24} = - \frac{11}{24} + 5\frac{1}{24} = 4\frac{14}{24} = 4\frac{7}{12}$$.
Ответ: $$4\frac{7}{12}$$