4.395 Найдите значение выражения: a) 0,9 * (-0,4) – 0,7 * (-0,4); б) -4/13 * 0,6 – 0,6 * (-9/13); в) -8/11 * 5/6 + 5/6 * 3/11; г) 1 2/3 * 2,8 – 2 2/9 * (-6,2); д) (4/7 – 3/5) * 35; е) (-1 1/3 – 1 1/9) * 18.

a) $0.9 \cdot (-0.4) - 0.7 \cdot (-0.4) = -0.36 + 0.28 = -0.08$ б) $-\frac{4}{13} \cdot 0.6 - 0.6 \cdot (-\frac{9}{13}) = -\frac{4}{13} \cdot \frac{6}{10} + \frac{6}{10} \cdot \frac{9}{13} = \frac{6}{10} \cdot (-\frac{4}{13} + \frac{9}{13}) = \frac{3}{5} \cdot \frac{5}{13} = \frac{3}{13}$ в) $-\frac{8}{11} \cdot \frac{5}{6} + \frac{5}{6} \cdot \frac{3}{11} = \frac{5}{6} \cdot (-\frac{8}{11} + \frac{3}{11}) = \frac{5}{6} \cdot (-\frac{5}{11}) = -\frac{25}{66}$ г) $1\frac{2}{3} \cdot 2.8 - 2\frac{2}{9} \cdot (-6.2) = \frac{5}{3} \cdot \frac{28}{10} + \frac{20}{9} \cdot \frac{62}{10} = \frac{5}{3} \cdot \frac{14}{5} + \frac{20}{9} \cdot \frac{31}{5} = \frac{14}{3} + \frac{4}{9} \cdot 31 = \frac{14}{3} + \frac{124}{9} = \frac{42 + 124}{9} = \frac{166}{9} = 18\frac{4}{9}$ д) $(\frac{4}{7} - \frac{3}{5}) \cdot 35 = (\frac{20 - 21}{35}) \cdot 35 = (-\frac{1}{35}) \cdot 35 = -1$ е) $(-1\frac{1}{3} - 1\frac{1}{9}) \cdot 18 = (-\frac{4}{3} - \frac{10}{9}) \cdot 18 = (-\frac{12 + 10}{9}) \cdot 18 = -\frac{22}{9} \cdot 18 = -22 \cdot 2 = -44$ **Ответ:** a) -0.08 б) 3/13 в) -25/66 г) 18 4/9 д) -1 е) -44