Calcule o valor de cada expressão abaixo: a) (4/3 - 1/5) + (5/4 - 1/3) b) 1 + (1/3 - 1/5) - (4/3 - 1/2) c) 3 1/4 + 2 1/2 - 4 1/6 d) (3 1/11 - 1) + ...

a) (4/3 - 1/5) + (5/4 - 1/3) = (20/15 - 3/15) + (15/12 - 4/12) = 17/15 + 11/12 = (204 + 165) / 180 = 369/180 = 41/20 b) 1 + (1/3 - 1/5) - (4/3 - 1/2) = 1 + (10/30 - 6/30) - (8/6 - 3/6) = 1 + 4/30 - 5/6 = 1 + 2/15 - 5/6 = (6 + 4 - 25) / 30 = -15/30 = -1/2 c) 3 1/4 + 2 1/2 - 4 1/6 = (13/4) + (5/2) - (25/6) = (39/12) + (30/12) - (50/12) = 19/12 d) (3 1/11 - 1) + (2 1/4 - 7/4) - (2 1/2 - 2 1/3) = (34/11 - 11/11) + (9/4 - 7/4) - (5/2 - 7/3) = (23/11) + (2/4) - (1/6) = (253 + 33 - 22) / 132 = 264/132 = 2