Bonjour pouvez m'aidez svp? CEST POUR DMN

Bonsoir,

III-
A = 3/5 + 2/7 x 3/10 + 2/7
A = 6/5 + 6/70 + 2/7
A = (6 x 14) / (5 x 14) + 6/70 + (2 x 10) / (7 x 10)
A = 84/70 + 6/70 + 20/70
A = 110/70
A = (10 x 11) / (10 x 7)
A = 11/7

B = 7/3 : 2/5 + 2/3
B = 7/3 x 5/2 + 2/3
B = 35/6 + 2/3
B = 35/6 + (2 x 2) / (3 x 2)
B = 35/6 + 4/6
B = 39/6
B = (3 x 13) / (3 x 2)
B = 13/2

C = 1/2 + 2/3 + 3/4
C = (1 x 6) / (2 x 6) + (2 x 2) / (3 x 2) + (3 x 3) / (4 x 3)
C = 6/12 + 4/12 + 9/12
C = 19/12

IV- J'y ai déjà répondu aujourd'hui