Data Sufficiency

if X>1 and Y>1, is X<Y?


(1) X^2/(XY+X)<1
(2) XY/Y^2-Y<1

OA : E

Can u please check if OA is [spoiler]B)[/spoiler] ?

I must be misisng something if not.... I will check again

I am getting B.. can u pls check the OA.
Here is my approach.

Cramya, Logitech. Pls let me know if I have messed up.


stmt 1:
x^2 / (xy -x) < 1
This can be simplified coz x and y != 0 (the min requirement)
so simplying
x/(y+1) < 1
= x < y+1

We are not sure whether x < y. since x < (y+1), x could be = y or >y

So insufficient.

Stmt2:
xy/(y^2 -y) < 1
again simplifying
x/(y-1) < 1
= x < y-1
x is less than y-1. Hence x is definitely less than y.
Sufficient.
B

Vittal, I think u r ok there!

stmt 2 can be solved as x < y-1 , as both positive, that sure implies x is less that y

I am too going with B

I confirm that B is the answer for me too...same conclusion as you!

vittalgmat wrote:I am getting B.. can u pls check the OA.
Here is my approach.

Cramya, Logitech. Pls let me know if I have messed up.


stmt 1:
x^2 / (xy -x) < 1
This can be simplified coz x and y != 0 (the min requirement)
so simplying
x/(y+1) < 1
= x < y+1

We are not sure whether x < y. since x < (y+1), x could be = y or >y

So insufficient.

Stmt2:
xy/(y^2 -y) < 1
again simplifying
x/(y-1) < 1
= x < y-1
x is less than y-1. Hence x is definitely less than y.
Sufficient.
B

vittalgmat, your solution looks good. But I hope you know why the sign did not change when you got:

x/(y-1) < 1
= x < y-1

Because you know that Y-1 is a positive number right ? Otherwise you could have gotten into trouble!

Yep I did Logitech.. Thanks for pointing me out.
I was 90% sure .. now coz u pointed it out, I will remember this!!

sorry guys, the sets aren't very reliable. At least not the ones I have.

sorry guys, the sets aren't very reliable. At least not the ones I have.

I agree. Its good to get it clarified when in doubt.

Regards,
Cramya