1\frac{1}{5} \cdot 3 + \frac{4}{5} \cdot 3; 2\frac{4}{5} \cdot \frac{5}{9} + 6\frac{1}{5} \cdot \frac{5}{9}; 3\frac{1}{5} \cdot \frac{8}{11} + 3\frac{1}{5} \cdot \frac{3}{11};

1.

• $$1\frac{1}{5} \cdot 3 + \frac{4}{5} \cdot 3 = \frac{6}{5} \cdot 3 + \frac{4}{5} \cdot 3$$
• $$\frac{6}{5} \cdot 3 + \frac{4}{5} \cdot 3 = \frac{18}{5} + \frac{12}{5}$$
• $$\frac{18}{5} + \frac{12}{5} = \frac{30}{5}$$
• $$\frac{30}{5} = 6$$

2.

• $$2\frac{4}{5} \cdot \frac{5}{9} + 6\frac{1}{5} \cdot \frac{5}{9} = \frac{14}{5} \cdot \frac{5}{9} + \frac{31}{5} \cdot \frac{5}{9}$$
• $$\frac{14}{5} \cdot \frac{5}{9} + \frac{31}{5} \cdot \frac{5}{9} = \frac{14 \cdot 5}{5 \cdot 9} + \frac{31 \cdot 5}{5 \cdot 9}$$
• $$\frac{14 \cdot 5}{5 \cdot 9} + \frac{31 \cdot 5}{5 \cdot 9} = \frac{70}{45} + \frac{155}{45}$$
• $$\frac{70}{45} + \frac{155}{45} = \frac{225}{45}$$
• $$\frac{225}{45} = 5$$

3.

• $$3\frac{1}{5} \cdot \frac{8}{11} + 3\frac{1}{5} \cdot \frac{3}{11} = \frac{1}{5} \cdot \frac{8}{11} + \frac{16}{5} \cdot \frac{3}{11}$$
• $$\frac{1}{5} \cdot \frac{8}{11} + \frac{16}{5} \cdot \frac{3}{11} = \frac{8}{55} + \frac{48}{55}$$
• $$\frac{8}{55} + \frac{48}{55} = \frac{56}{55}$$
• $$\frac{56}{55} = 1\frac{1}{55}$$

Ответ: 1) 6; 2) 5; 3) 1\frac{1}{55}