When a jug is 1/5 full and it weighs 250 grams next it 4/5 full and weighs 550 grams what is the weight of the jug?

X=weight of the jug
y=witht of liquid when the jug is full
we suggest this system of equations:
x+y/5=250
x+4y/5=550
we solve this system of equations by equalization method. 
x=250-y/5
x=550-4y/5
250-y/5=550-4y/5
least common multiple=5
1250-y=2750-4y
-y+4y=2750-1250
3y=1500
y=1500/3
y=500 

x=250-y/5
x=250-500/5
x=250-100
x=150

weight of the jug = 150grams. 

Dis the correct answer