Răspuns :

a+b=600
a:b=4
a=4b si inlocuim in suma
4b+b=600
5b=600
b=120  a=480
x+y=600
x:y=4
x=4y
4y+y=600
5y=600
y=600:5
y=120
x+120=600
x=600-120
x=480