Répondre :

A=4/3+7/6 = 8/6 + 7/6 = 15/6 = 5/2
B=13/5+6/3 = 39/15 + 30/15 = 69/15 = 23/5
C=3+7/4 = 19/4
D=7/9-5/6 = 42/54 - 45/54 = -3/54 = -1/18