Explications étape par étape:
a)2/7 et 3/8
2/7 = (2 x 8)/(7 x 8) = 16/56
3/8 = (3 x 7)/(8 x 7) = 21/56
/boxed{2/7 different de 3/8}/boxed2/7differentde3/8
b)5/4 et 6/11
5/4 = (5 x 11)/(4 x 11) = 55/44
6/11 = (6 x 4)/(11 x 4) = 24/44
\boxed{5/4 different de 6/11}5/4differentde6/11
