Réponse :
Bonjour
Explications étape par étape
6)
A = 2/3 + 1/4
A = (2×4)/(3×4) + (1×3)/(4×3)
A = 8/12 + 3/12
A = 11/12
B = 3/8 + 2/5
B = (3×5)/(8×5) + (2×8)/(5×8)
B = 15/40 + 16/40
B = 31/40
C = 5/6 - 2/7
C = (5×7)/(6×7) - (2×6)/(7×6)
C = 35/42 - 12/42
C = 23/42
D = 11/15 - 4/7
D = (11×7)/(15×7) - (4×15)/(7×15)
D = 77/105 - 60/105
D = 17/105
7)
2/10 + 1/10 + 3/10 = 6/10
1 - 6/10 = 10/10 - 6/10 = 4/10
les 4/10 représentent l'alcool soit 4/10 × 100 = 40% d'alcool.
