б) $$-2\frac{2}{3} + 2\frac{1}{3} \cdot \left( -15\frac{3}{7} - (-4,8) \right) : \frac{4}{12}$$
1) $$-15\frac{3}{7} = -\frac{15 \cdot 7 + 3}{7} = -\frac{108}{7}$$
2) $$-4,8 = -\frac{48}{10} = -\frac{24}{5}$$
3) $$-15\frac{3}{7} - (-4,8) = -\frac{108}{7} + \frac{24}{5} = \frac{-108 \cdot 5 + 24 \cdot 7}{35} = \frac{-540 + 168}{35} = \frac{-372}{35}$$
4) $$2\frac{1}{3} = \frac{7}{3}$$
5) $$\frac{4}{12} = \frac{1}{3}$$
6) $$\frac{7}{3} \cdot \frac{-372}{35} : \frac{1}{3} = \frac{7}{3} \cdot \frac{-372}{35} \cdot 3 = \frac{7 \cdot -372}{35} = \frac{-372}{5} = -74,4$$
7) $$-2\frac{2}{3} = -\frac{8}{3}$$
8) $$-2\frac{2}{3} + 2\frac{1}{3} \cdot \left( -15\frac{3}{7} - (-4,8) \right) : \frac{4}{12} = -\frac{8}{3} - 74,4 = -2,6 - 74,4 = -77$$
Ответ: -77