Bonjour
A=1 - 2/7 + 2/7 + 2/7 : 7/14
A = 1 - 2/7 + 2/7 + 2/7 x 14/7
A = 1 - 2/7 + 2/7 + 28/49
A= (1 x 7) / (1 x 7) + 4/7 + (7 x 4) / (7 x 7)
A = 7/7 + 4/7 + 4/7
A = 15/7
B=
2/3 + -11/6
——————-
3 x 4/9
B = [(2 x 2) / (3 x 2) - 11/6] : 12/9
B = (4/6 - 11/6) : 12/9
B = - 7/6 x 9/12
B = - 63/72
B = (9 x - 7) / (9 x 8)
B = - 7/8
C= 4 - (1/30 - 1/6) : 1/3
C = 4 - [1/30 - (1 x 5) / (6 x 5)] : 1/3
C = 4 - (1/30 - 5/30) : 1/3
C = 4 - (- 4/30) : 1/3
C = 4 - (- 4/30) x 3
C = 4 + 12/30
C = (4 x 30) / (1 x 30) + 12/30
C = 120/30 + 12/30
C = 132/30
C = (6 x 22) / (6 x 5)
C = 22/5
D= 7/3 - 10/3 x 28/35
D = 7/3 - 280/105
D = 7/3 - (35 x 8) / (35 x 3)
D = 7/3 - 8/3
D = - 1/3
E= 7/8 x 16/14 - 4/5
E = 112/112 - 4/5
E = 1 - 4/5
E = (1 x 5) / (1 x 5) - 4/5
E = 5/5 - 4/5
E = 1/5.