comment rangé ces fractions dans croissant 13/11, 11/19, 13/7, 3/19, 13/9, 17/17, 18/19 .

13/11 = 1,19
11/19 = 0,56
13/7 = 1,86
3/19 = 0,16
13/9 = 1,44
17/17 = 1
18/19 = 0,95
3/19 < 11/19 < 18/19 < 17/17 < 13/11 < 13/9 < 13/7
voilà