de l'aide pour l'exercice 1 svp

1)
E = - 48/78
E = 6 x (- 8) / 6 x 13
E = - 8/13

F = - 15,3/ - 7,5
F = 15,3/7,5
F = 15,3 x 10 / 7,5 x 10
F = 153/75
F = 3 x 51 / 3 x 25
F = 51/25

2)
M = 2/9 + - 5 / - 6
M = 2/9 + 5/6
M = 2 x 2 / 9 x 2 + 5 x 3 / 6 x 3
M = 4/18 + 15/18
M = 19/18

N = 7/6 - - 5/8
N = 7/6 + 5/8
N = 7 x 8 / 6 x 8 + 5 x 6 / 8 x 6
N = 56/48 + 30/48
N = 86/48
N = 2 x 43 / 2 x 24
N = 43/24

P = (5/6 + - 1/3) - (7/12 + 5/3)
P = (5 x 2 / 6 x 2 - 1 x 4 / 3 x 4) - (7/12 + 5 x 4 / 3 x 4)
P = (10/12 - 4/12) - (7/12 + 20/12)
P = 6/12 - 27/12
P = - 19/12