Alina + George + Diana = 348 castane ( total)
George = 2 x Alina
Diana = George+13
Metoda grafica
nr. castane Alina l--------l
castane George l--------l--------l } total =348
castane Diana l--------l--------l+13
348 - 13 = 335 suma celor 5 parti egale
335 : 5 = 67 castane a cules Alina
2 x 67 = 134 castane a cules George
134 + 13 = 147 castane a cules Diana