9. \(8\frac{1}{10}-2\frac{3}{10}-1\frac{5}{10}\)

\[8\frac{1}{10}-2\frac{3}{10}-1\frac{5}{10}=8\frac{1}{10}-3\frac{8}{10}=4\frac{3}{10}.\]

Ответ: \(4\frac{3}{10}\).