- \(1-\frac{2}{7}=\frac{7}{7}-\frac{2}{7}=\frac{5}{7}\).
- \(8-\frac{1}{9}=\frac{72}{9}-\frac{1}{9}=\frac{71}{9}=7\frac{8}{9}\).
- \(4-\frac{3}{8}=\frac{32}{8}-\frac{3}{8}=\frac{29}{8}=3\frac{5}{8}\).
- \(11-\frac{2}{5}=\frac{55}{5}-\frac{2}{5}=\frac{53}{5}=10\frac{3}{5}\).
Ответ: \(\frac{5}{7};\ 7\frac{8}{9};\ 3\frac{5}{8};\ 10\frac{3}{5}\).