2 вариант 1. Выполните действие: а) 57 ⋅ 69 ; б) 11 7 ⋅ 28 33 ; ? 51 3 в) 3⋅1; 713 2 г) 2⋅6; 3 9; 816 15 е) : 5. 16

Ответ: а) \(\frac{35}{54}\); б) \(\frac{11}{44} = \frac{1}{4}\); в) \(\frac{140}{13}\); г) \(\frac{14}{3}\); д) \(\frac{3}{2}\); е) \(\frac{15}{80} = \frac{3}{16}\).

1. а) \(\frac{5}{6} \cdot \frac{7}{9} = \frac{5 \cdot 7}{6 \cdot 9} = \frac{35}{54}\)
2. б) \(\frac{11}{28} \cdot \frac{7}{33} = \frac{11 \cdot 7}{28 \cdot 33} = \frac{1 \cdot 1}{4 \cdot 3} = \frac{1}{12}\)
3. в) \(3\frac{5}{7} \cdot 1\frac{1}{13} = \frac{26}{7} \cdot \frac{14}{13} = \frac{26 \cdot 14}{7 \cdot 13} = \frac{2 \cdot 2}{1 \cdot 1} = 4\)
4. г) \(2\frac{2}{3} \cdot 6 = \frac{8}{3} \cdot 6 = \frac{8 \cdot 6}{3} = \frac{8 \cdot 2}{1} = 16\)
5. д) \(\frac{3}{8} : \frac{9}{16} = \frac{3}{8} \cdot \frac{16}{9} = \frac{3 \cdot 16}{8 \cdot 9} = \frac{1 \cdot 2}{1 \cdot 3} = \frac{2}{3}\)
6. е) \(\frac{15}{16} : 5 = \frac{15}{16} \cdot \frac{1}{5} = \frac{15}{16 \cdot 5} = \frac{3}{16}\)

Ответ: а) \(\frac{35}{54}\); б) \(\frac{11}{44} = \frac{1}{4}\); в) \(\frac{140}{13}\); г) \(\frac{14}{3}\); д) \(\frac{3}{2}\); е) \(\frac{15}{80} = \frac{3}{16}\).