г) Выполним вычитание: $$2\frac{5}{6} - 3\frac{3}{8}$$;
$$2\frac{5}{6} = \frac{2 \times 6 + 5}{6} = \frac{17}{6}$$
$$3\frac{3}{8} = \frac{3 \times 8 + 3}{8} = \frac{27}{8}$$
$$\frac{17}{6} - \frac{27}{8} = \frac{17 \times 4}{6 \times 4} - \frac{27 \times 3}{8 \times 3} = \frac{68}{24} - \frac{81}{24} = -\frac{13}{24}$$
Ответ: $$\frac{-13}{24}$$