Решение

a) $$\frac{6}{13} \cdot 19\frac{1}{2} = \frac{6}{13} \cdot \frac{39}{2} = \frac{6 \cdot 39}{13 \cdot 2} = \frac{6 \cdot 3}{2} = 3 \cdot 3 = 9$$

б) $$1\frac{10}{11} \cdot 3\frac{1}{7} = \frac{21}{11} \cdot \frac{22}{7} = \frac{21 \cdot 22}{11 \cdot 7} = \frac{3 \cdot 2}{1} = 6$$

в) $$0.4 \cdot 3\frac{1}{3} = \frac{4}{10} \cdot \frac{10}{3} = \frac{4}{3} = 1\frac{1}{3}$$

г) $$0.6 \cdot \frac{2}{3} = \frac{6}{10} \cdot \frac{2}{3} = \frac{2}{5} \cdot \frac{2}{1} = \frac{4}{5}$$

д) $$(0.3 + 0.5) \cdot 1\frac{1}{2} = 0.8 \cdot 1.5 = \frac{8}{10} \cdot \frac{15}{10} = \frac{4}{5} \cdot \frac{3}{2} = \frac{2}{5} \cdot 3 = \frac{6}{5} = 1.2$$

e) $$(1.3 - 0.7) \cdot 1\frac{2}{3} = 0.6 \cdot \frac{5}{3} = \frac{6}{10} \cdot \frac{5}{3} = \frac{3}{5} \cdot \frac{5}{3} = 1$$