bonjour
soit x la somme de départ
- BD = x - 49
- Pain = x - 49 - 1.10 = x - 50.10
- cousin = x - 50.10 + 3 = x - 47.10
- sucreries = ( x - 47.10 ) / 2 = 0.5 x - 23.55
S = 0.5 x - 23.55 = 4 .70
0.5 x = 4.7 + 23 .55
0. 5x = 28.25
x = 56.50
il avait 56.50 €