are they Positive ??

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are they Positive ??

by Khaim » Thu Jul 16, 2009 4:02 pm
Are x and y both positive ?

1) 2x - 2y = 0

2) x/y > 1


Can someone explain me with calculation how to find this ?

Thank you :)
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by Khaim » Thu Jul 16, 2009 4:03 pm
Are x and y both positive ?

1) 2x - 2y = 1

2) x/y > 1


Can someone explain me with calculation how to find this ?

Thank you


SORRY THE FIRST POST IS WRONG
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by shibal » Thu Jul 16, 2009 4:12 pm
IMO E... by plug in numbers it can be both positive or negatve

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by tohellandback » Thu Jul 16, 2009 4:15 pm
IMO E
1)2x - 2y = 1
or x=1/2 + Y now x and y can be +ve or -ve. take examples y=-5 and y=10
INSUFF
2) it just tells you that x>y both can be positive. x=20, y=10
or both can be negative- x=-20,y=-10
INSUFF

combining
x>y
and
x=1/2 + Y- in this eq positive or negative X is always greater than Y
The powers of two are bloody impolite!!

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by Khaim » Thu Jul 16, 2009 4:19 pm
I also answered E ...

But the correct answer is C !! I dont know why

the question is from the GMATprep software exam 1
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by tohellandback » Thu Jul 16, 2009 4:34 pm
Khaim wrote:I also answered E ...

But the correct answer is C !! I dont know why

the question is from the GMATprep software exam 1
oops sorry I got it..
It has to be C. I did a mistake
1)2x - 2y = 1
or x=1/2 + Y now x and y can be +ve or -ve. take examples y=-5 and y=10
INSUFF
2) x>y when both are positive
x<y when both are negative

combining
x=1/2 + Y- in this eq positive or negative X is always greater than Y
so from 2 x>y i.e. both are positive
The powers of two are bloody impolite!!

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by mehravikas » Thu Jul 16, 2009 5:15 pm
Statement 1 -

Simplify the expression 2x – 2y = 1

X = y + ½

Not sufficient

Statement 2 –

X/Y > 1
X = -5, y = -2 result > 1
X = 5, y = 2 result > 1

Not sufficient

Combining the statements – x = y + ½
(Y + ½ ) / y > 1

1 + 1/2y > 1

1/2y > 1 – 1 = 1/2y > 0

i.e. y > 0 therefore x has to be positive as well. Answer C