1)
x=k/2
y=k/5
z=k/8
k/2+k/5+k/8=330
20k+8k+5k=13200
33k=13200
k=400
x=k/2=400/2=200
y=k/5=400/5=80
z=k/8=400/8=50
2)
10 kg portocale ...........6 l suc
32 kg portocale ...........x l suc
x=32*6/10=192/10=19,2 kg suc
3) 300 km : 40 km/h=7,5 ore
7,5 ore x 60 km/h=450 km