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Source: Beat The GMAT — Data Sufficiency |
- logitech
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I am not a big fan of plugging numbers but how about -1/2 ?jayjk78 wrote:stm 1. try x=2, -2, 1/2 the only way for stm 1 to be true is x=2 ie sufficient and |x| not less than 1
stm 2. not sufficient...x=-2 and x=-1/2 both can be true
Hence a
LGTCH
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4meonly
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If x is not equal to 0, is |x| less than 1?
(1) ( x / |x| ) < x
(2) |x| > x
Good question
I first picked A and then stopped to check - that saved me
Question:
|x| < 1?
(1)
(x/|x|)<x
multiply both sides by |x|
x < x*|x|
here are 2 options:
a. x>0 (e.g. 5)
divide both sides by x with 1 < |x| as a result
b. x<0 (e.g. -1/2)
divide both sides by x with 1 > |x| as a result
2 options thus INSUFF
(2)
|x| > x
this means that x<0 but it not gives us anuthing about the value of x
(1)(2)
x<0 (from 2)
1 > |x| (from 1)
so, -1<x<0
SUFF
C
(1) ( x / |x| ) < x
(2) |x| > x
Good question
I first picked A and then stopped to check - that saved me
Question:
|x| < 1?
(1)
(x/|x|)<x
multiply both sides by |x|
x < x*|x|
here are 2 options:
a. x>0 (e.g. 5)
divide both sides by x with 1 < |x| as a result
b. x<0 (e.g. -1/2)
divide both sides by x with 1 > |x| as a result
2 options thus INSUFF
(2)
|x| > x
this means that x<0 but it not gives us anuthing about the value of x
(1)(2)
x<0 (from 2)
1 > |x| (from 1)
so, -1<x<0
SUFF
C
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bluementor
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Wow, this question really got me!... Nice explanation 4meonly!
Logitech, where's this question from?
-BM-
Logitech, where's this question from?
-BM-
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jimmiejaz
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One more approach logitech....logitech wrote:Could you please explain your approach ?cramya wrote:I get C) OA please?
we know value of |x| will be always positive.
so,
when x>0, x/x < x or x>1
when x<0, x/-x < x or x>-1
hence insuff as we want to know if -1<x<1
from 2nd we get x<0 as 0<0 not possible when x>0
its also insuff....
combining we get
-1<x<0 hence suff...
C
hope it helps....
- logitech
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Good discussions guys. Problem is from Manhattan GMAT.logitech wrote:If x is not equal to 0, is |x| less than 1?
(1) ( x / |x| ) < x
(2) |x| > x
OA C
So the question is asking if X is between - 1 and + 1 ( EXCLUDING zero )
1)
if x<0
x / |x| = -1 So, x>-1
---> -1 < x < 0
If x > 0
x / |x| = 1 So, x > 1
INSUF
2) Basically tells us X < 0
So 1&2
we know that X < 0 and -1 < x < 0
Thank you all!
LGTCH
---------------------
"DON'T LET ANYONE STEAL YOUR DREAM!"
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"DON'T LET ANYONE STEAL YOUR DREAM!"












