Respuesta :
Carmen,
Places avió = P
Prefrent = 3/4P
Turista = 1/4P
Preferent ocupades: 40% de 3/4P = 2/5x3/4P = 3/10P
Turista ocupades = 70% = 7/10x1/4P = 7/40P
3/10P + 7/40P = 228
(12/40 + 7/40)P = 228
19P = 228x40
P = 480
Número pleces avió = 480
Places avió = P
Prefrent = 3/4P
Turista = 1/4P
Preferent ocupades: 40% de 3/4P = 2/5x3/4P = 3/10P
Turista ocupades = 70% = 7/10x1/4P = 7/40P
3/10P + 7/40P = 228
(12/40 + 7/40)P = 228
19P = 228x40
P = 480
Número pleces avió = 480