1. Вычислите: а) \(\frac{8}{14}+\frac{1}{28}\); б) \(\frac{4}{15}-\frac{3}{25}\); в) \(\frac{5}{40}+\frac{4}{69}\).

1. а) \(\frac{8}{14}+\frac{1}{28}=\frac{4}{7}+\frac{1}{28}=\frac{16}{28}+\frac{1}{28}=\frac{17}{28}\).
2. б) \(\frac{4}{15}-\frac{3}{25}=\frac{20}{75}-\frac{9}{75}=\frac{11}{75}\).
3. в) \(\frac{5}{40}+\frac{4}{69}=\frac{1}{8}+\frac{4}{69}=\frac{69}{552}+\frac{32}{552}=\frac{101}{552}\).

Ответ: а) \(\frac{17}{28}\); б) \(\frac{11}{75}\); в) \(\frac{101}{552}\).