4) Mp=(3x5/3+4x11/4+5x19/5)/(3+4+5)=
=(5+11+19)/12=35/12=2,91(6)
5) x-cant.de marfa din magazie
I zi : x-4x/9=(9x-4x)/9=5x/9
II zi :5x/9-2/5·(5x/9)=5x/9-2x/9=3x/9=x/3
IiIzi : x/3-1/4·(x/3)=x/3-x/12=(4x-x)/12=3x/12=x/4
x/4=1125
x=1125·4
x=4500 kg
I zi s-a scos: 4500x4/9=2000 kg
II zi: (4500-2000)x2/5=1000kg
III zi: (2500-1000)x1/4=375
1000+2000+375+1125=4500