Calculer les sommes suivantes A=5/4+7/8. B=-2/5+7/15 C=8/18+ -7/6. D= -5/32+ -3/8 Merci d'avance.

A=2,125
B=13/15 (en fraction car c'est un nombre infini)
C=-13/18
D=-0.53125

A = 5/4 +7/8
A = 5/4 X 2/2 +7/8
A = 10/8 + 7/8
A = 17/8

B = -2/5 +7/15
B = -2/5 X 3/3 +7/15
B = -6/15 +7/15
B = 2/15

C = 8/18 + -7/6
C = 8/18 -7/6 X 3/3
C = 8/18 -21/18
C = -13/8

D = -5/32 + -3/8
D = -5/32 -3/8 X 4/4
D = -5/32 -12/32
D = -17/32