$$c - \frac{5}{9}c + 4\frac{5}{6}c = c - \frac{5}{9}c + \frac{4 \cdot 6 + 5}{6}c = c - \frac{5}{9}c + \frac{29}{6}c = \frac{1 \cdot 18}{18}c - \frac{5 \cdot 2}{9 \cdot 2}c + \frac{29 \cdot 3}{6 \cdot 3}c = \frac{18}{18}c - \frac{10}{18}c + \frac{87}{18}c = \frac{18 - 10 + 87}{18}c = \frac{95}{18}c$$
Если $$c = 7\frac{1}{5}$$, то $$\frac{95}{18} \cdot 7\frac{1}{5} = \frac{95}{18} \cdot \frac{7 \cdot 5 + 1}{5} = \frac{95}{18} \cdot \frac{36}{5} = \frac{95 \cdot 36}{18 \cdot 5} = \frac{19 \cdot 5 \cdot 18 \cdot 2}{18 \cdot 5} = 19 \cdot 2 = 38$$
Ответ: 38