Răspuns :
a+b+c=600
a+b=300 => c = 600 - 300 = 300
b+c=500 => a = 600 - 500 = 100
a+b=300 => b = 300 - 100 = 200
Pai...
a+b+c=600
a+b=300
b+c=500
deci:
a+b=300⇒c=600-300⇒c=300
b+c=500⇒a=600-500⇒a=100
a+b=300=>b=300-100⇒b=200
deci:
a+b+c=600
100+200+300=300+300=600