1) (-9,7+7,1):(-1\frac{4}{9}); 2) (3\frac{1}{8}-2\frac{5}{12})\cdot(-1\frac{3}{17}).

Решение:

• 1) \[ (-9,7+7,1):\left(-1\frac{4}{9}\right) \]
  • \[ -9,7+7,1 = -2,6 \]
  • \[ -2,6 = -\frac{26}{10} = -\frac{13}{5} \]
  • \[ -1\frac{4}{9} = -\frac{13}{9} \]
  • \[ \left(-\frac{13}{5}\right):\left(-\frac{13}{9}\right) = \frac{13}{5} \cdot \frac{9}{13} = \frac{9}{5} = 1,8 \]
• 2) \[ \left(3\frac{1}{8}-2\frac{5}{12}\right)\cdot\left(-1\frac{3}{17}\right) \]
  • \[ 3\frac{1}{8} = \frac{25}{8} \]
  • \[ 2\frac{5}{12} = \frac{29}{12} \]
  • \[ \frac{25}{8} - \frac{29}{12} = \frac{75}{24} - \frac{58}{24} = \frac{17}{24} \]
  • \[ -1\frac{3}{17} = -\frac{20}{17} \]
  • \[ \frac{17}{24} \cdot \left(-\frac{20}{17}\right) = -\frac{20}{24} = -\frac{5}{6} \]

Ответ: 1) 1,8; 2) -\frac{5}{6}.