Question

in trei butoaie sunt 210l de vin. in primele doua sunt 130l,iar in ultimile doua 150l.cati litri de vin sunt in fiecare butoi?

Answer 1

I+II+III=210
I+II=130
II+III=150
1.Cati l sunt in al treilea butoi?
 210-130=80
2.Cati l sunt in primul butoi?
 210-150=60
3.Cati l sunt in al doilea butoi?
  130-60=70
 Proba: 80+60+70=210

Answer 2

a+b+c=210l
a+b    =130l
    b+c=150l
a=?,b=?,c=?
c=210l-130l
c=80l
a=210l-150l
a=60l
b=130l-60l
b=70l