1. Выполните действия: 1) 4/7 + 5/6; 2) 5/18 + 7/30; 3) 15/19 + 27/38; 4) 5/12 + 2/15; 5) 13/25 + 7/10; 6) 4/21 + 5/7; 7) 8/9 + 7/12; 8) 0,22 + 3/25 + 1/20; 9) 1/45 + 0,3 + 11/50; 10) 7/11 − 7/12; 11) 7/15 − 2/5; 12) 11/21 − 3/14; 13) 11/16 − 5/12; 14) 8/21 − 4/35; 15) 7/24 − 5/18; 16) 11/63 − 5/42.

Для сложения и вычитания дробей приводим их к общему знаменателю. Десятичные дроби представляем обыкновенными или используем общий знаменатель.

1. \(\frac{4}{7}+\frac{5}{6}=\frac{24}{42}+\frac{35}{42}=\frac{59}{42}=1\frac{17}{42}\).
2. \(\frac{5}{18}+\frac{7}{30}=\frac{25}{90}+\frac{21}{90}=\frac{46}{90}=\frac{23}{45}\).
3. \(\frac{15}{19}+\frac{27}{38}=\frac{30}{38}+\frac{27}{38}=\frac{57}{38}=1\frac{19}{38}=1\frac{1}{2}\).
4. \(\frac{5}{12}+\frac{2}{15}=\frac{25}{60}+\frac{8}{60}=\frac{33}{60}=\frac{11}{20}\).
5. \(\frac{13}{25}+\frac{7}{10}=\frac{26}{50}+\frac{35}{50}=\frac{61}{50}=1\frac{11}{50}\).
6. \(\frac{4}{21}+\frac{5}{7}=\frac{4}{21}+\frac{15}{21}=\frac{19}{21}\).
7. \(\frac{8}{9}+\frac{7}{12}=\frac{32}{36}+\frac{21}{36}=\frac{53}{36}=1\frac{17}{36}\).
8. \(0{,}22+\frac{3}{25}+\frac{1}{20}=\frac{22}{100}+\frac{12}{100}+\frac{5}{100}=\frac{39}{100}\).
9. \(\frac{1}{45}+0{,}3+\frac{11}{50}=\frac{10}{450}+\frac{135}{450}+\frac{99}{450}=\frac{244}{450}=\frac{122}{225}\).
10. \(\frac{7}{11}-\frac{7}{12}=\frac{84}{132}-\frac{77}{132}=\frac{7}{132}\).
11. \(\frac{7}{15}-\frac{2}{5}=\frac{7}{15}-\frac{6}{15}=\frac{1}{15}\).
12. \(\frac{11}{21}-\frac{3}{14}=\frac{22}{42}-\frac{9}{42}=\frac{13}{42}\).
13. \(\frac{11}{16}-\frac{5}{12}=\frac{33}{48}-\frac{20}{48}=\frac{13}{48}\).
14. \(\frac{8}{21}-\frac{4}{35}=\frac{40}{105}-\frac{12}{105}=\frac{28}{105}=\frac{4}{15}\).
15. \(\frac{7}{24}-\frac{5}{18}=\frac{21}{72}-\frac{20}{72}=\frac{1}{72}\).
16. \(\frac{11}{63}-\frac{5}{42}=\frac{22}{126}-\frac{15}{126}=\frac{7}{126}=\frac{1}{18}\).