1. Выполните умножение дробей: a) $$28\frac{6}{19} \cdot 5\frac{7}{6}$$; б) $$38\frac{9}{22} \cdot 11\frac{15}{19}$$; в) $$0,4 \cdot 14\frac{19}{33}$$; г) $$13\frac{5}{8} \cdot 1\frac{11}{15}$$

1. a) $$28\frac{6}{19} \cdot 5\frac{7}{6} = \frac{28 \cdot 19 + 6}{19} \cdot \frac{5 \cdot 6 + 7}{6} = \frac{538}{19} \cdot \frac{37}{6} = \frac{269 \cdot 37}{19 \cdot 3} = \frac{9953}{57} = 174\frac{11}{57}$$ б) $$38\frac{9}{22} \cdot 11\frac{15}{19} = \frac{38 \cdot 22 + 9}{22} \cdot \frac{11 \cdot 19 + 15}{19} = \frac{845}{22} \cdot \frac{224}{19} = \frac{845 \cdot 112}{11 \cdot 19} = \frac{94640}{209} = 452\frac{72}{209}$$ в) $$0,4 \cdot 14\frac{19}{33} = \frac{4}{10} \cdot \frac{14 \cdot 33 + 19}{33} = \frac{2}{5} \cdot \frac{481}{33} = \frac{2 \cdot 481}{5 \cdot 33} = \frac{962}{165} = 5\frac{137}{165}$$ г) $$13\frac{5}{8} \cdot 1\frac{11}{15} = \frac{13 \cdot 8 + 5}{8} \cdot \frac{1 \cdot 15 + 11}{15} = \frac{109}{8} \cdot \frac{26}{15} = \frac{109 \cdot 13}{4 \cdot 15} = \frac{1417}{60} = 23\frac{37}{60}$$