Réponse :
C= 2x15/3x20
C = (2 x 3 x 5) / (3 x 2 x 2 x 5)
C = 1/2
D= 9x8/4x15
D = (3 x 3 x 2 x 2 x 2) / (2 x 2 x 3 x 5)
D = (3 x 2) /5
D = 6/5
E= 15x9/6x25
E = (3 x 5 x 3 x 3) / (2 x 3 x 5 x 5)
E = 9 / 10
F= 16/3 x 6/24
F = (4 x 4 x 2 x 3) / ( 3 x 2 x 4 x 3)
F = 4/3
H = 12 x 11/12
H = 11