Bonjour vous pouvez m'aider svp ? A = (1-1/7) : 12/5 B = 15 - 6/7 x 2/5 c = 3 + 5/4 x (2- 1/5) D = 25/17 : 15/14 - 11/3 Mer

bonjour

a = ( 7/7 - 1/7) : 12/5
A = 6/7 x 5/12
A = 30/84
A = 5/14

B = 15-12/35
B = 525/35 - 12/35 = 513/35

C = 3 + 10/-20 
C = 60/20 - 10/20 = 50/20 = 5/2

D = 25/14 x 14/15 - 11/3
D = 350/210 -11/3
D = 5/3 -11/3 = - 6/3 = -2

A = (1-1/7) : 12/5
A = (7/7-1/7) : 12/5
A = 6/7 : 12/5
A = 6/7x5/12
A = 5/714

 B = 15 - 6/7 x 2/5
B = 15-12/35
B = 15x35/35-12/35
B = 525-12/35
B = 513/35

c = 3 + 5/4 x (2- 1/5)
C = 12/4+5/4 x(10/5-1/5)
C =17/4 x 9/5
C = 17x9/(4x5)
C = 153/20

 D = 25/17 : 15/14 - 11/3
D = 25/17:  15x3/14x3 - 11x14/14x3
D = 25/17 : 45/42-154/42
D = 25/17 : -109/14
D = -25x14/17x109
D = -350/1853