3 mingi.......7 masinute......224 lei
3 mingi........4 masinute......146 lei
_________________________ ( - )
// 3 masinute......78 lei
Aflam cat costa o masinuta
78 : 3 = 26 lei
Aflam cat costa 7 masinute
7×26 = 182 lei
Aflam cat costa o minge
( 224-182) :3 = 42 : 3 = 14 lei
Verificare:
3×14+7×26 = 42+182 = 224
3×14+ 4×26 = 42 + 104 = 146