$$3 \frac{1}{11} \cdot 4 \frac{2}{5} + 1 \frac{5}{11} \cdot 4 \frac{2}{5} = (3 \frac{1}{11} + 1 \frac{5}{11}) \cdot 4 \frac{2}{5}$$
Вынесем общий множитель за скобки: $$4 \frac{2}{5}$$.
$$3 \frac{1}{11} + 1 \frac{5}{11} = 4 \frac{6}{11}$$
$$4 \frac{6}{11} \cdot 4 \frac{2}{5} = \frac{44+6}{11} \cdot \frac{20+2}{5} = \frac{50}{11} \cdot \frac{22}{5}$$
$$\frac{50}{11} \cdot \frac{22}{5} = \frac{10}{1} \cdot \frac{2}{1} = 20$$
Ответ: 20
$$2 \frac{3}{8} \cdot 3 \frac{1}{13} + \frac{5}{12} \cdot 3 \frac{1}{13} - 3 \frac{1}{13} \cdot 1 \frac{1}{6} = 3 \frac{1}{13} \cdot (2 \frac{3}{8} + \frac{5}{12} - 1 \frac{1}{6})$$
Вынесем общий множитель за скобки: $$3 \frac{1}{13}$$.
$$2 \frac{3}{8} + \frac{5}{12} - 1 \frac{1}{6} = 2 \frac{9}{24} + \frac{10}{24} - 1 \frac{4}{24} = 1 \frac{19}{24} + \frac{10}{24} = 1 \frac{29}{24} - \frac{4}{24} = 1 + 1 \frac{5}{24} = 2 \frac{5}{24}$$
$$3 \frac{1}{13} \cdot 2 \frac{5}{24} = \frac{39+1}{13} \cdot \frac{48+5}{24} = \frac{40}{13} \cdot \frac{53}{24} = \frac{5}{13} \cdot \frac{53}{3} = \frac{265}{39}$$
$$\frac{265}{39} = 6 \frac{31}{39}$$
Ответ: $$6 \frac{31}{39}$$