Réponse:
Bonjour,
A= 11/48+5/12
5/12×8/8=40/48
11/48+40/48=41/48
B= 5/14+13/7
13/7×2/2=26/14
5/14+26/14=31/14
C= 8/3-4/21
8/3×7/7=56/21
56/21-4/21=52/21
D= 4+5/11
4/1×11/11=44/11
44/11+5/11=49/11
E= 17/24-3/8
3/8×3/3=9/24
17/24-9/24=8/24=1/3
F= 3-7/13
3/1×13/13=39/13
39/13-7/13=32/12=8/3