Réponse :
A= 12/5 + 3/5 x 7/9 B= (2 + 4/5 - 7/10) x (7/2 - 3/2)
= 15/5 x 7/9 = (2 + 8/10 - 7/10) x 4/2
= 3 x 7/9 = 2 + -1/10 x 4/2
= 21/9 = 19/10 x 2
= 7/3 = 19/5
C = -2/3x (4/5 -3/20) D = -4/9 x 24/12 + 16/8 x 5/-4
= -8/15x + 1/10x = -8/9 - 5/2
=-16/30x + 3/30x = -16/18 - 45/18
= -13/30x = 61/18
