Ответ:

а) \(−9\frac{3}{4} : 1\frac{1}{12} = −\frac{39}{4} : \frac{13}{12} = −\frac{39}{4} \cdot \frac{12}{13} = −9\).

б) \(13\frac{3}{5} : (−1,7) = \frac{68}{5} : \left(−\frac{17}{10}\right) = \frac{68}{5} \cdot \left(−\frac{10}{17}\right) = −8\).

в) \(1\frac{1}{5} \cdot (−1,2) = \frac{6}{5} \cdot \left(−\frac{6}{5}\right) = −\frac{36}{25} = −1,44\).

г) \(−8\frac{1}{7} : 1\frac{1}{5} = −\frac{57}{7} : \frac{6}{5} = −\frac{57}{7} \cdot \frac{5}{6} = −\frac{95}{14} = −6\frac{11}{14}\).

Ответ: а) −9; б) −8; в) −1,44; г) −6 11/14.