Bonsoir,
i. 2/3 < 5/3
j. 19/23 < 31/23
k. 1/3 < 3
3 = (3 x 3) / (1 x 3) = 9/3
l. 7/13 < 13/7
7/13 = (7 x 7) / (13 x 7) = 49/91 et 13/7 = (13 x 13) / (7 x 13) = 169/91
m. 12/15 < 26/30
12/15 = (12 x 2) / (15 x 2) = 24/30
n. 1/2 > 1/4
1/2 = (1 x 2) / (2 x 2) = 2/4
o. 12/15 < 12/3
12/3 = (12 x 5) / (3 x 5) = 60/15
p. 7/18 > 3/9
3/9 = (3 x 2) / (9 x 2) = 6/18
q. 19/10 < 10/5
10/5 = (10 x 2) / (5 x 2) = 20/10