bonjour,
A = - 1/2 - ( - 7/3 )
A = - 1/2 + 7/3
A = - 3/6 + 14/6
A = 11 /6
B = 2/5 : 5/7
B = 2/5 * 7/5
B = 14/35
C = 21/66 * 55*35
C = 1155/2310
C = 1 /2
D = - 7/16 + 5/12 * 3
D = 7/16 + 15/12
D = 21/48 + 60/48
D = 81 /48
D = 27/16
E = 4/7 - 1/7 : ( 2 + 5/2)
E = 4/7 - 1 /7 : ( 4/2 + 5/2)
E = 4 /7 - 1 /7 : 7/2
E = 4/7 - 1/7 * 2/7
E = 4/7 - 2/49
E = 28/49 - 2 /49
E = 26/49
