1) $$0,8 \cdot \frac{7}{12} = \frac{8}{10} \cdot \frac{7}{12} = \frac{4}{5} \cdot \frac{7}{12} = \frac{4 \cdot 7}{5 \cdot 12} = \frac{1 \cdot 7}{5 \cdot 3} = \frac{7}{15}$$
Ответ: $$\frac{7}{15}$$
2) $$1\frac{2}{3} \cdot 0,6 = \frac{5}{3} \cdot \frac{6}{10} = \frac{5 \cdot 6}{3 \cdot 10} = \frac{1 \cdot 2}{1 \cdot 2} = 1$$
Ответ: 1
3) $$1,25 \cdot \frac{32}{45} = \frac{125}{100} \cdot \frac{32}{45} = \frac{5}{4} \cdot \frac{32}{45} = \frac{5 \cdot 32}{4 \cdot 45} = \frac{1 \cdot 8}{1 \cdot 9} = \frac{8}{9}$$
Ответ: $$\frac{8}{9}$$
4) $$4,5 - 3\frac{1}{3} = \frac{45}{10} - \frac{10}{3} = \frac{9}{2} - \frac{10}{3} = \frac{9 \cdot 3}{2 \cdot 3} - \frac{10 \cdot 2}{3 \cdot 2} = \frac{27}{6} - \frac{20}{6} = \frac{27-20}{6} = \frac{7}{6} = 1\frac{1}{6}$$
Ответ: $$1\frac{1}{6}$$