Réponse :
Bonjour ;
Explications étape par étape
a) 3x4/40 +7x5/40 =47/40
b) 5x3/8x3 +7x2/12x2 = 15/24 +14/24 = 29/24
c) 11x7/6x7 +5x2/21x2 = 77/42 +10/42 = 87/42
d) 11x7/9x7 -1x3/21x3 = 77/63 -3/63 = 74/63
e) 11x5/15x5 -4x3/25x3=55/75 -12/75 = 34/75
F) 13x5/14x5 -9x2/35x2 = 45/70 -18/70 = 27/70
