a) -$$\frac{1}{6}$$ + $$\frac{2}{3}$$ = -$$\frac{1}{6}$$ + $$\frac{4}{6}$$ = $$\frac{3}{6}$$ = $$\frac{1}{2}$$ = 0.5
б) -$$\frac{4}{5}$$ + (-$$\frac{1}{10}$$) = -$$\frac{8}{10}$$ - $$\frac{1}{10}$$ = -$$\frac{9}{10}$$ = -0.9
в) $$\frac{3}{8}$$ - $$\frac{3}{4}$$ = $$\frac{3}{8}$$ - $$\frac{6}{8}$$ = -$$\frac{3}{8}$$ = -0.375
г) 1,2-12,3 = -11.1
д) -0,25-(-1,2) = -0,25+1,2 = 0.95
e) -17,9+3,12 = -14.78