Ответ:
- \(\frac{7}{9}+\frac{7}{27}=\frac{21}{27}+\frac{7}{27}=\frac{28}{27}=1\frac{1}{27}\).
- \(\frac{5}{6}-\frac{2}{9}=\frac{15}{18}-\frac{4}{18}=\frac{11}{18}\).
- \(\frac{3}{7}\cdot\frac{4}{9}=\frac{12}{63}=\frac{4}{21}\).
- \(\frac{4}{7}:\frac{3}{8}=\frac{4}{7}\cdot\frac{8}{3}=\frac{32}{21}=1\frac{11}{21}\).
- \(\frac{11}{20}-\frac{7}{30}=\frac{33}{60}-\frac{14}{60}=\frac{19}{60}\).
- \(\frac{5}{7}:\frac{12}{8}=\frac{5}{7}\cdot\frac{8}{12}=\frac{10}{21}\).
Ответ: а) \(1\frac{1}{27}\); б) \(\frac{11}{18}\); в) \(\frac{4}{21}\); г) \(1\frac{11}{21}\); д) \(\frac{19}{60}\); е) \(\frac{10}{21}\).
