Greatest Integer

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Greatest Integer

by colakumarfanta » Tue May 25, 2010 3:11 am
[X] denotes Greatest Integer Function greater than or equal to X , Is X-[X]> 0?
(1) X is positive
(2) X is not an integer

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by gmatmachoman » Tue May 25, 2010 3:26 am
colakumarfanta wrote:[X] denotes Greatest Integer Function greater than or equal to X , Is X-[X]> 0?
(1) X is positive
(2) X is not an integer

Indeed D

st 1:X is positive

case 1 : 0.2

[x]= 1

X-[X] =0.2-1 = -0.8<0 ( so the given function is NOT greater than 0)

case 2: 1.9
[x] = 2

1.9-2 = -0.2 <0

Sufficient . We are left with A or D

st 2: X is not an integer

X = -5.5

[x] = -5

X-[X]

-5.5 - (-5)

-0.5 < 0 ( so the given function is NOT greater than 0)

Sufficient

Pick D

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by liferocks » Tue May 25, 2010 3:51 am
I will go with B

From statement 1

X is positive ,hence if x is not integer X<[X] or X-[X]<0 0
but if X is an integer then X=[X] then X-[X]=0...not sufficient

From statement 2

if X is negative X<[X] or X-[X]<0
if X is positive X<[X] or X-[X]<0...sufficient

What is OA?
"If you don't know where you are going, any road will get you there."
Lewis Carroll

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by gmatmachoman » Tue May 25, 2010 3:56 am
liferocks wrote:I will go with B

From statement 1

X is positive ,hence if x is not integer X<[X] or X-[X]<0 0
but if X is an integer then X=[X] then X-[X]=0...not sufficient


What is OA?
Yeah , so X will be less than or equal to zero..rite?? and In No way it can be greater than zero!!

Wat say LR???

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by liferocks » Tue May 25, 2010 4:00 am
gmatmachoman wrote:
liferocks wrote:I will go with B

From statement 1

X is positive ,hence if x is not integer X<[X] or X-[X]<0 0
but if X is an integer then X=[X] then X-[X]=0...not sufficient


What is OA?
Yeah , so X will be less than or equal to zero..rite?? and In No way it can be greater than zero!!

Wat say LR???
Yes sir.you are correct.should have thought that.Thanks for pointing out...I think its time for me to take a break :evil:
"If you don't know where you are going, any road will get you there."
Lewis Carroll

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by gmatmachoman » Tue May 25, 2010 4:07 am
liferocks wrote:
gmatmachoman wrote:
liferocks wrote:I will go with B

From statement 1

X is positive ,hence if x is not integer X<[X] or X-[X]<0 0
but if X is an integer then X=[X] then X-[X]=0...not sufficient


What is OA?
Yeah , so X will be less than or equal to zero..rite?? and In No way it can be greater than zero!!

Wat say LR???
Yes sir.you are correct.should have thought that.Thanks for pointing out...I think its time for me to take a break

:evil:

oh oh ohhhh...when did I become sir!!!??? I am not one..hehehehe!! dude is very much preferbale..else Govi is most welcome as i am called by our BTGians!!

LR ..to be really true, it gives me great sense of happiness when i post a single answer ahead of u which i was sharing with one of my buddy over here...!!

Thanks!

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by liferocks » Tue May 25, 2010 4:10 am
gmatmachoman wrote:
liferocks wrote:
gmatmachoman wrote:
liferocks wrote:I will go with B

From statement 1

X is positive ,hence if x is not integer X<[X] or X-[X]<0 0
but if X is an integer then X=[X] then X-[X]=0...not sufficient


What is OA?
Yeah , so X will be less than or equal to zero..rite?? and In No way it can be greater than zero!!

Wat say LR???
Yes sir.you are correct.should have thought that.Thanks for pointing out...I think its time for me to take a break

:evil:

oh oh ohhhh...when did I become sir!!!??? I am not one..hehehehe!! dude is very much preferbale..else Govi is most welcome as i am called by our BTGians!!

LR ..to be really true, it gives me great sense of happiness when i post a single answer ahead of u which i was sharing with one of my buddy over here...!!

Thanks!
I will see how long it will be there when I come back...cu..after the break :mrgreen:
"If you don't know where you are going, any road will get you there."
Lewis Carroll

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by Patrick_GMATFix » Tue May 25, 2010 6:50 am
colakumarfanta wrote:[X] denotes Greatest Integer Function greater than or equal to X , Is X-[X]> 0?
(1) X is positive
(2) X is not an integer
Please verify the text of the question. If the text of the question is correct, please provide the source.

The question tells us that [X] is greater than or equal to X.

[X] >= X means 0 >= X - [X]. In other words, the difference X-[X] will never be greater than 0. It can at most be equal to 0.

The question can be answered without even looking at the statements. This situation will never happen on the exam. The mathematics aside, the syntax of the question is very poor. This is not a GMAT caliber question; if I were in your shoes, I would stop using the source of this Q as it is not properly preparing you for the GMAT.

If the question was not copied correctly, please provide the correct content as well as the source.

Please consider studying from Official materials. They provide plenty of practice: OGs, old paper tests, and most of all GMATPrep (best resemblance to the real exam). You can use this forum, the GMATFix tools, or Manhattan GMAT's tools to extend the utility of the official materials.

-Best of luck,
Patrick