Răspuns :
Fie a prima fractie cautata si b a doua.
a+b=12.8
a=3b
Inlocuim in prima relatie => 3b+b=12.8 => 4b=12.8 =>b=(12.8)/4=3.2=32/10=16/5 si a=3*16/5=48/5
a+b=12.8
a=3b
Inlocuim in prima relatie => 3b+b=12.8 => 4b=12.8 =>b=(12.8)/4=3.2=32/10=16/5 si a=3*16/5=48/5