Найдите произведение или частное. a) 9/10 * 5/12 б) 11/5 : 15/6 в) 9/22 * 2/3 г) 7/8 : 7/16 д) 27/40 : 18/35 е) 8/9 : 6 ж) 15 * 5/6 з) 1 1/7 : 12 и) 2 * 12/3 к) 2/3 : 18 л) 8/27 * 36 м) 10 : 4/15

Выполним действия с дробями: а) $$rac{9}{10} \cdot \frac{5}{12} = \frac{9 \cdot 5}{10 \cdot 12} = \frac{45}{120} = \frac{3}{8}$$ б) $$\frac{11}{5} \div \frac{15}{6} = \frac{11}{5} \cdot \frac{6}{15} = \frac{11 \cdot 6}{5 \cdot 15} = \frac{66}{75} = \frac{22}{25}$$ в) $$\frac{9}{22} \cdot \frac{2}{3} = \frac{9 \cdot 2}{22 \cdot 3} = \frac{18}{66} = \frac{3}{11}$$ г) $$\frac{7}{8} \div \frac{7}{16} = \frac{7}{8} \cdot \frac{16}{7} = \frac{7 \cdot 16}{8 \cdot 7} = \frac{16}{8} = 2$$ д) $$\frac{27}{40} \div \frac{18}{35} = \frac{27}{40} \cdot \frac{35}{18} = \frac{27 \cdot 35}{40 \cdot 18} = \frac{3 \cdot 7}{8 \cdot 2} = \frac{21}{16} = 1\frac{5}{16}$$ е) $$\frac{8}{9} \div 6 = \frac{8}{9} \div \frac{6}{1} = \frac{8}{9} \cdot \frac{1}{6} = \frac{8 \cdot 1}{9 \cdot 6} = \frac{8}{54} = \frac{4}{27}$$ ж) $$15 \cdot \frac{5}{6} = \frac{15}{1} \cdot \frac{5}{6} = \frac{15 \cdot 5}{1 \cdot 6} = \frac{75}{6} = \frac{25}{2} = 12\frac{1}{2}$$ з) $$1 \frac{1}{7} \div 12 = \frac{8}{7} \div 12 = \frac{8}{7} \div \frac{12}{1} = \frac{8}{7} \cdot \frac{1}{12} = \frac{8 \cdot 1}{7 \cdot 12} = \frac{8}{84} = \frac{2}{21}$$ и) $$2 \cdot \frac{12}{3} = \frac{2}{1} \cdot \frac{12}{3} = \frac{2 \cdot 12}{1 \cdot 3} = \frac{24}{3} = 8$$ к) $$\frac{2}{3} \div 18 = \frac{2}{3} \div \frac{18}{1} = \frac{2}{3} \cdot \frac{1}{18} = \frac{2 \cdot 1}{3 \cdot 18} = \frac{2}{54} = \frac{1}{27}$$ л) $$\frac{8}{27} \cdot 36 = \frac{8}{27} \cdot \frac{36}{1} = \frac{8 \cdot 36}{27 \cdot 1} = \frac{8 \cdot 4}{3 \cdot 1} = \frac{32}{3} = 10 \frac{2}{3}$$ м) $$10 \div \frac{4}{15} = \frac{10}{1} \div \frac{4}{15} = \frac{10}{1} \cdot \frac{15}{4} = \frac{10 \cdot 15}{1 \cdot 4} = \frac{150}{4} = \frac{75}{2} = 37\frac{1}{2}$$