bonjour
Tarif A = 15 + 4 x
Tarif B = 35 + 2 x
1 a) 5 films tarif A = 15 + 20 = 35 €
1 b) 10 films tarif B = 35 + 20 = 55 €
1 c) 15 films tarif A = 15 + 60 = 75 €
15 films tarif B = 35 +30 = 65 €
2) 2/5 + 1/4 = 8/20 + 5/20 = 13/20 donc 7/20 prennent le tarif C
3) tarif A = 300 x 2/5 = 240 personnes
tarif B = 600 : 4 = 150 personnes
tarif C = 600 x 7/20 = 210 personnes