Question

Avem la dispozitie baloane de trei culori: rosii, albastre si verzi. Punand la un loc baloanele rosii si albastre, obtinem 60 de baloane. Punand la un loc baloanele rosii si verzi, obtinem 70 de baloane. Punand la un loc baloanele verzi si albastre obtinem 80 de baloane. Cate baloane de fiecare fel avem?

Answer 1

r+a= 60
r+v=70
v+a=80 / +
2r+2a+2v=60+70+80
2(r+a+v)=210
r+a+v=210:2
r+a+v=105
60+v=105
v=105-60=45
r+45=70
r=70-45
r=25
a+45=80
a=80-45
a=35

Answer 2

r+a= 60
r+v= 70
v+a= 80
2a+2r+2v= 60+70+80
2(a+r+v)= 210=> a+r+v= 105
a+ 70= 105=> a= 35
r+a= 60=> r+ 35= 60=> r= 25
r+v= 70=> 25+v= 70=> v= 45