Вариант I 1. Вычислите: a) $$1\frac{1}{2} \cdot 1\frac{1}{3}$$; б) $$1\frac{1}{3} : 1\frac{8}{4}$$; в) $$1\frac{1}{9} \cdot 2\frac{2}{5}$$; г) $$8 : 1\frac{7}{9}$$; д) $$3\frac{1}{2} : 1\frac{1}{6}$$

a) $$1\frac{1}{2} \cdot 1\frac{1}{3} = \frac{3}{2} \cdot \frac{4}{3} = \frac{3 \cdot 4}{2 \cdot 3} = \frac{12}{6} = 2$$

б) $$1\frac{1}{3} : 1\frac{3}{8} = \frac{4}{3} : \frac{11}{8} = \frac{4}{3} \cdot \frac{8}{11} = \frac{4 \cdot 8}{3 \cdot 11} = \frac{32}{33}$$

в) $$1\frac{1}{9} \cdot 2\frac{2}{5} = \frac{10}{9} \cdot \frac{12}{5} = \frac{10 \cdot 12}{9 \cdot 5} = \frac{120}{45} = \frac{8}{3} = 2\frac{2}{3}$$

г) $$8 : 1\frac{7}{9} = 8 : \frac{16}{9} = 8 \cdot \frac{9}{16} = \frac{8 \cdot 9}{16} = \frac{72}{16} = \frac{9}{2} = 4\frac{1}{2}$$

д) $$3\frac{1}{2} : 1\frac{1}{6} = \frac{7}{2} : \frac{7}{6} = \frac{7}{2} \cdot \frac{6}{7} = \frac{7 \cdot 6}{2 \cdot 7} = \frac{42}{14} = 3$$