Réponse :
A = 5/6 - 1/3
A = (5x3)/(6x3) - (1x6)/(3x6) = 15/18 - 6/18 = 9/18 = (3x3)/(3x6) = 3/6 = (3x1)/(3x2) = 1/2
B = -3/4 + 7/24
B = (-3 x 6)/(4x6) + 7/24 = -18/24 + 7/24 = -11/24
C = -8/45 - 2/5
C = -8/45 - (2 x 9)/(5x9) = -8/45 - 18/45 = -26/45
D = 9/14 - 5
D = 9/14 - (5x14)/(1x14) = 9/14 - 60/14 = - 51/14
E = 1/6 - 17/30 + 4/5
E = (1x5)/(6x5) - 17/30 + (4x6)/(5x6) = 5/30 - 17/30 + 24/30 = 12/30 = (3x4)/(3x10) = 4/10 = (2x2)/(2x5) = 2/5
F = 21/25 - 3/5
F = 21/25 - (3x5)/(5x5) = 21/25 - 15/25 = 6/25
Explications étape par étape