4kg mere+5kg portocale= 190 lei
3kg mere+ 2kg portocale=90 lei
1kg mere+ 1kg portocale=x
--------
7kg mere+7 kg portocale= 280 lei
7(1 kg mere+1 kg portocale)=280lei
1kg mere+1 kg portocale=280/7
1kg mere+1 kg portocale=40 lei
Probleme de clasa a 4 a