а) (1-1/2):(1/2-1/3) = (1-0.5):(0.5-0.33) = 0.5/0.17 = 2.94
б) (1/2+1/4-2/5):(4/5) = (0.5+0.25-0.4):(0.8) = 0.35/0.8 = 0.4375
в) 3/4:(1-1/4+3/8) = 0.75:(0.75) = 1
г) (1/3+1/4):(2-5/6) = (0.33+0.25):1.33 = 0.58/1.33 = 0.4368
а) (1-1/2):(1/2-1/3) = (1-0.5):(0.5-0.33) = 0.5/0.17 = 2.94
б) (1/2+1/4-2/5):(4/5) = (0.5+0.25-0.4):(0.8) = 0.35/0.8 = 0.4375
в) 3/4:(1-1/4+3/8) = 0.75:(0.75) = 1
г) (1/3+1/4):(2-5/6) = (0.33+0.25):1.33 = 0.58/1.33 = 0.4368