Lets look at each statement separately.
(1) x = 0.5 + y
This does not tell us anything about the values of x and y. Only the relation between them. Therefore, insufficient.
(2) x/y > 1
lets use some numbers
x=2, y=0.5 x/y=4>2
x=-2, y=-0.5 x/y=4>2.
Therefore, insufficient.
(1)+(2)
lets place the first equation in the second:
(0.5+y)/y=0.5/y + 1>1
0.5/y>0
So we know that y>0 therefore, x=y+0.5>0.5
Therefore, C
x/y
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Source: Beat The GMAT — Data Sufficiency |
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sanjay_dce
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stmt1: obviously not sufficient .billyr wrote:Are x and y both positive?
(1) 2x-2y=1
(2) x/y>1
The answer is c, but i thought it should be E .
thanks
stmt 2 : x & y both can be -ve and both could be +ve, only thing it tells that both need to be of same sign and mod x > mod y
using both 1 &2 only option left is both x and y are +ve and X>Y hence C is correct
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x2suresh
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clearly individual statements not sufficientbillyr wrote:Are x and y both positive?
(1) 2x-2y=1
(2) x/y>1
The answer is c, but i thought it should be E .
thanks
combined
2x-2y=1 --> divide by 2y throught out the equation.
x/y-1 = 1/2y
we know that x/y>1 eqn(2)
clearly 1/2y >1 --> y is +ve
if y is +ve clearly from eqn 2x-2y=1
x is +Ve
sufficient
C.
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sureshbala
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Clearly each statement alone is not sufficient.
From I: x=y+1
From II: x/y>1
i.e (y+1)/y >1
i.e 1+1/y >1
So y>0.
Since x =y+1, x>0
Hence C is the answer
From I: x=y+1
From II: x/y>1
i.e (y+1)/y >1
i.e 1+1/y >1
So y>0.
Since x =y+1, x>0
Hence C is the answer
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x2suresh
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sureshbala wrote:Clearly each statement alone is not sufficient.
From I: x=y+1
From II: x/y>1
i.e (y+1)/y >1
i.e 1+1/y >1
So y>0.
Since x =y+1, x>0
Hence C is the answer
how did you get x=y+1 from eqn(1) 2x-2y=1 ??
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sureshbala
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luckylucky
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Are x and y both positive?
(1) 2x-2y=1
(2) x/y>1
Frens please correct me if i am wrong in my approach
1) 2x - 2y = 1
= > x - y = 0.5
Plug in values that satisfy the above equation
a) x = -3 y = -3.5
It satisfies the equation and both x , y <0
b) x = 4 y = 3.5
It satisfies the equation and both x ,y >0
Hence A alone is not sufficient
2) x/y > 1
= > x > y
a) x = 4 y = 3.5 x,y >0
b) x = -3 y = -3.5 x,y < 0
Hence B alone is not sufficient
Combining both A and B
x - y = 0.5 & x > y
a) x = 4 and y = 3.5 x,y > 0
b) x = -3 and y = -3.5 x,y < 0
Hence the answer should be E
I am not able to get C with the above approach . Can someone pleas explain where am i going wrong ?
(1) 2x-2y=1
(2) x/y>1
Frens please correct me if i am wrong in my approach
1) 2x - 2y = 1
= > x - y = 0.5
Plug in values that satisfy the above equation
a) x = -3 y = -3.5
It satisfies the equation and both x , y <0
b) x = 4 y = 3.5
It satisfies the equation and both x ,y >0
Hence A alone is not sufficient
2) x/y > 1
= > x > y
a) x = 4 y = 3.5 x,y >0
b) x = -3 y = -3.5 x,y < 0
Hence B alone is not sufficient
Combining both A and B
x - y = 0.5 & x > y
a) x = 4 and y = 3.5 x,y > 0
b) x = -3 and y = -3.5 x,y < 0
Hence the answer should be E
I am not able to get C with the above approach . Can someone pleas explain where am i going wrong ?
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kamu
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exactly!!!!luckylucky wrote:Are x and y both positive?
(1) 2x-2y=1
(2) x/y>1
Frens please correct me if i am wrong in my approach
1) 2x - 2y = 1
= > x - y = 0.5
Plug in values that satisfy the above equation
a) x = -3 y = -3.5
It satisfies the equation and both x , y <0
b) x = 4 y = 3.5
It satisfies the equation and both x ,y >0
Hence A alone is not sufficient
2) x/y > 1
= > x > y
a) x = 4 y = 3.5 x,y >0
b) x = -3 y = -3.5 x,y < 0
Hence B alone is not sufficient
Combining both A and B
x - y = 0.5 & x > y
a) x = 4 and y = 3.5 x,y > 0
b) x = -3 and y = -3.5 x,y < 0
Hence the answer should be E
I am not able to get C with the above approach . Can someone pleas explain where am i going wrong ?
please explain!!!
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sureshbala
- Master | Next Rank: 500 Posts
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- Joined: Wed Feb 04, 2009 10:32 am
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Folk, look at the bold statements....luckylucky wrote:Are x and y both positive?
(1) 2x-2y=1
(2) x/y>1
Frens please correct me if i am wrong in my approach
1) 2x - 2y = 1
= > x - y = 0.5
Plug in values that satisfy the above equation
a) x = -3 y = -3.5
It satisfies the equation and both x , y <0
b) x = 4 y = 3.5
It satisfies the equation and both x ,y >0
Hence A alone is not sufficient
2) x/y > 1
= > x > y
a) x = 4 y = 3.5 x,y >0
b) x = -3 y = -3.5 x,y < 0
Hence B alone is not sufficient
Combining both A and B
x - y = 0.5 & x > y
a) x = 4 and y = 3.5 x,y > 0
b) x = -3 and y = -3.5 x,y < 0
Hence the answer should be E
I am not able to get C with the above approach . Can someone pleas explain where am i going wrong ?
If x/y > 1, then we can conclude that x>y provided x and y are positive. This is what you missed.
Looking at your example (in bold), if x= -3 and y = -3.5 , how can x/y >1? Instead it will be less than...
Hope you got it....
