Réponses

2014-03-13T18:50:46+01:00
Bonsoir

- librairie + magasin de sport = 1/3 +1/4 = 4/12 + 3/12 = 7/12
- il lui reste : 12/12 -7/12 = 5/12

30 € = 5/12
12/12 = (12 x 30)/5 = 72 €