3. Вычислите: а) - 3/-0,84-3-2,16; 8) (-3+31)-18; 2 9 11 г) 9 12 11 1 47 6) -11; (一)

а) \[\frac{2}{3} \cdot (-0.84) - \frac{4}{3} \cdot 2.16 = \frac{2}{3} \cdot (-0.84) - \frac{4}{3} \cdot 2.16 = \frac{-1.68 - 8.64}{3} = \frac{-10.32}{3} = -3.44\]

б) \[\left(-\frac{2}{9} + 3\frac{1}{18}\right) \cdot 18 = \left(-\frac{4}{18} + \frac{55}{18}\right) \cdot 18 = \frac{51}{18} \cdot 18 = 51\]

в) \[\left(-0.7 - 1\frac{1}{11}\right) \cdot 11 = \left(-\frac{7}{10} - \frac{12}{11}\right) \cdot 11 = \left(-\frac{77 + 120}{110}\right) \cdot 11 = \frac{-197}{10} = -19.7\]