media ponderata=(12/3x3+23/4x4+34/5x5):(3+4+5)=
simplificam si obtinem
(12+23+34):12=69:12=5,75
5)
cantitatea totala de marfa =,,a"
I zi=4/9xa=4a/9
raman a-4a/9=(9a-4a)9=5a/9
a II zi=2/5x5a/9=2a/9
raman 5a/9-2a/9=3a/9 simplificam=a/3
aIII a zi=1/4xa/3=a/12
raman a/3-a/12=(4a-a)/12=3a/12=a/4
a/4=1125
a=1125x4
a=4500 kg
6)(1x10grade+3x30grade):4litri=(10+90):4=100:4=25 grade