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Bonjour

F = 3/4 + 13/20

F = (3 x 5) / (4 x 5) + 13/20

F = 15/20 + 13/20

F = 28/20

F = (4 x 7) / (4 x 5)

F = 7/4

G = 7/8 - 1/6

G = (7 x 3) / (8 x 3) - (1 x 4) / (6 x 4)

G = 21/24 - 4/24

G = 17/24

H = 2 - 4/5 + 2/3

H = (2 x 15) / (1 x 15) - (4 x 3) / (5 x 3) + (2 x 5) / (3 x 5)

H = 30/15 - 12/15 + 10/15

H = 40/15 - 12/15

H = 28/15