Ответ:

  1. \(\frac{2}{5}-\frac{1}{10}=\frac{4}{10}-\frac{1}{10}=\frac{3}{10}\).
  2. \(\frac{3}{8}-\frac{1}{6}=\frac{9}{24}-\frac{4}{24}=\frac{5}{24}\).
  3. \(11-\frac{7}{15}=10+\frac{15}{15}-\frac{7}{15}=10\frac{8}{15}\).