Please help if you can!
Are x and y both positive?
(1) 2x - 2y = 1
(2) (x/y) > 1
Naturally, I can eliminate both on their own, but testing to see if both or neither are sufficient is time consuming. Does anyone have any tips to get through this question quickly? I got it right after about 3 mins of work
From 1-> x=(2y+1)/2 . form this statement we cannot say that x and y are both positive.
From 2 -> (x/y)>1. So the value of x is y+something. But still its insufficient.
From both the statements combine we have x=(2y+1)/2 and (x/y)>1.
Now x/y = [(2y+1)/2]/y = (2y+1)/2y = 1+1/2y.
This expression shows that when y is +ve then and only then is the value of x/y >1. So answere is C.