Is X>0?
1) XY>0
2) X+Y>0
I picked E. However the OA is C...
I know that from statement 1, X and Y either have to be both (-) or both (+), and statement 2 tells us that X>Y...but couldnt X still be negative and larger than Y? Ex: X is -2, Y is -4, AND X can be (+) and still bigger than Y...what am i missing?
thank yoU!
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Number Properties Gmat Prep question confusing...
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mustbeatgmat
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Rahul@gurome
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Statement 2 is (X + Y) > 0. Which tells us X > -Y not X > Ymustbeatgmat wrote:Is X>0?
1) XY>0
2) X+Y>0
I picked E. However the OA is C...
I know that from statement 1, X and Y either have to be both (-) or both (+), and statement 2 tells us that X>Y...but couldnt X still be negative and larger than Y? Ex: X is -2, Y is -4, AND X can be (+) and still bigger than Y...what am i missing?
thank yoU!
If X = -2 and Y = -4, statement doesn't satisfies.
The solution is as follows:
Statement 1: xy > 0
Implies,
- (1) x > 0 and y > 0
(2) x < 0 and y < 0
Statement 2: x + y > 0
Implies,
- (1) x > 0 and y > 0
(2) x > 0 and y < 0 and |x| > |y|
(3) x < 0 and y > 0 and |x| < |y|
1 & 2 together: Only possibility is x > 0 and y > 0.
Sufficient.
The correct answer is C.
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Rezinka
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Taking Statement I and II together :
When :
1)
X and Y both are positive :
XY > 0................... Possible
X + Y > 0............... Possible
2)
X and Y both are negative :
XY > 0................... Possible
X + Y > 0............... Not Possible
The sum of 2 negative numbers cannot be a positive number.
Hence we only have 1 option.
When :
1)
X and Y both are positive :
XY > 0................... Possible
X + Y > 0............... Possible
2)
X and Y both are negative :
XY > 0................... Possible
X + Y > 0............... Not Possible
The sum of 2 negative numbers cannot be a positive number.
Hence we only have 1 option.
