1. Раскройте скобки и вычислите: a) -(18 – 6); б) -6 + (-2 + 7); в) -(-9,1 – 1,1); г)* -(3$$\frac{11}{18}$$ – 5,7) + (4$$\frac{17}{18}$$ + 2,3).

a) $$-(18 - 6) = -18 + 6 = -12$$ б) $$-6 + (-2 + 7) = -6 + 5 = -1$$ в) $$-(-9.1 - 1.1) = -(-10.2) = 10.2$$ г) $$-(3\frac{11}{18} - 5.7) + (4\frac{17}{18} + 2.3) = -(3 + \frac{11}{18} - 5.7) + (4 + \frac{17}{18} + 2.3) = -3 - \frac{11}{18} + 5.7 + 4 + \frac{17}{18} + 2.3 = (-3 + 4 + 5.7 + 2.3) + (\frac{17}{18} - \frac{11}{18}) = (1 + 8) + \frac{6}{18} = 9 + \frac{1}{3} = 9\frac{1}{3}$$