Bonsoir
D = 1 - (1/4 +3/4 x 4/5)
= 1 - ( 1/4 + 12/20= = 1 - (5/20+12/20) = 1 -17/20 = 20/20-17/20 = 3/20
En 2001 : vendu 1/4, il reste donc 3/4
a) en 2002, vendu 4/5 de 3/4 = 4/5 x 3/4 = 12/20 = 3/5
b) reste invendu : 1 -(1/4+3/5) = 1 - (5/20+12/20) = 1 -17/20 = 20/20-17/20 = 3/20
c) 3/20 = 6ha donc 20/20 = 40 ha
d) 6ha = 60 000m² donc 60 000 x 160 = 9 600 000 euros