Question

In trei butoaiesunt sunt 200 l de vin in primele doua sunt 130 l iar in ultimele doua 150 l.Cati l de vin sunt in fiecare buto?

Answer 1

200-150=50 l(primul butoi)
200-120=80 l(al trilea butoi)
200-(80+50)=70 l(al doilea butoi)

Answer 2

a+b+c=200;
a+b=130;
b+c=150;
⇒c=[a+b+c]-[a+b]
⇒c=200-130
⇒c=70[litri-de vin-al treilea butoi];
⇒b=[b+c]-c
⇒b=150-70
⇒b=80[litri-de vin-al doilea butoi];
⇒a=[a+b]-b
⇒a=130-80
⇒a=50[litri-de vin-primul butoi];