Решение:
- \(\frac{7}{10}-\frac{4}{10} = \frac{7-4}{10} = \frac{3}{10}\)
- \(\frac{8}{9}-\frac{5}{9} = \frac{8-5}{9} = \frac{3}{9} = \frac{1}{3}\)
- \(\frac{57}{88}-\frac{14}{88} = \frac{57-14}{88} = \frac{43}{88}\)
Ответ: а) \(\frac{3}{10}\); б) \(\frac{1}{3}\); в) \(\frac{43}{88}\)