15kg cartofi......12 kg varza.......69 lei
5kg cartofi........7kg varza..........29 lei
15kg cartofi....12kg varza.......69 lei
15kg cartofi....21kg varza......87lei
/ 9kg varza=18 lei
18:9=2lei(1kg varza)
2ori12=24lei(12 kg varza)
69-24=45lei(15 kg cartofi)
45:15=3 lei (1kg cartofi)