Вычислите: а) 1/4 + 5/8; б) 7/9 + 7/27; в) 6/7 − 3/4; г) 1/3 + 3/5; д) 11/20 − 7/30; е) 5/8 − 7/12.

1. а) \(\frac{1}{4}+\frac{5}{8}=\frac{2}{8}+\frac{5}{8}=\frac{7}{8}\).
2. б) \(\frac{7}{9}+\frac{7}{27}=\frac{21}{27}+\frac{7}{27}=\frac{28}{27}=1\frac{1}{27}\).
3. в) \(\frac{6}{7}-\frac{3}{4}=\frac{24}{28}-\frac{21}{28}=\frac{3}{28}\).
4. г) \(\frac{1}{3}+\frac{3}{5}=\frac{5}{15}+\frac{9}{15}=\frac{14}{15}\).
5. д) \(\frac{11}{20}-\frac{7}{30}=\frac{33}{60}-\frac{14}{60}=\frac{19}{60}\).
6. е) \(\frac{5}{8}-\frac{7}{12}=\frac{15}{24}-\frac{14}{24}=\frac{1}{24}\).

Ответ: а) \(\frac{7}{8}\); б) \(1\frac{1}{27}\); в) \(\frac{3}{28}\); г) \(\frac{14}{15}\); д) \(\frac{19}{60}\); е) \(\frac{1}{24}\).