GMAT Data Sufficiency (DS) | Re: Is x > 3y?

x>3y? Yes/No?
a) x/y > 3
Here we can't multiply y on right side as we don't know the polarity of y.
So there are two cases -
1) if y is positive:
x/y > 3
x > 3y
2) if y is negative:
x/y>3
x < 3y
So, there are two possibilities and there is no definite Yes/No answer - so A is not sufficient.

b) y>0
We don't know about x.
x could be greater than y, equal to y, less than y - so, B is not sufficient.
Now, combine a) and b)
We know from a) y could be positive
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