prouver vous m'expliquer la façon de calculer car je n'ai pas compris comment il faut simplifier. Merci d'avance​

Bonjour,

E = 6/5 x 9/42

E = 54/210

E = (6 x 9) / (6 x 35)

E = 9/35

F = 20/7 x 14/15

F = 280/105

F = (35 x 8) / (35 x 3)

F = 8/3

G = 12/49 x 7/3

G = 84/147

G = (21 x 4) / (21 x 7)

G = 4/7

H = 45/4 x 4/5

H = 180/20

H = (20 x 9) / (20 x 1)

H = 9

I = 8 x 9/32

I = 72/32

I = (8 x 9) / (8 x 4)

I = 9/4

J = 3/4 x 4/3

J = 12/12

J = 1.