GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 20 Jul 2018, 11:43

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Is x an integer?

Author Message
TAGS:

### Hide Tags

Manager
Status: May The Force Be With Me (D-DAY 15 May 2012)
Joined: 06 Jan 2012
Posts: 246
Location: India
Concentration: General Management, Entrepreneurship

### Show Tags

Updated on: 12 Jun 2013, 03:19
2
00:00

Difficulty:

5% (low)

Question Stats:

83% (00:26) correct 17% (00:35) wrong based on 180 sessions

### HideShow timer Statistics

Is x an integer?

(1) x/2 is an integer
(2) 2x is an integer

I used a fraction (4/2) in A to prove that X is not an integer but OA is different

_________________

Giving +1 kudos is a better way of saying 'Thank You'.

Originally posted by boomtangboy on 04 Feb 2012, 10:43.
Last edited by Bunuel on 12 Jun 2013, 03:19, edited 2 times in total.
Edited the question
Manager
Joined: 03 Oct 2009
Posts: 52
Re: X is an integer?  [#permalink]

### Show Tags

04 Feb 2012, 11:01
Is X an integer?

A] X/2 is an integer
Sufficient, X is a multiple of 2.

B] 2X is an integer
Not sufficient, for instance x = .5 and 2x = 1.
Math Expert
Joined: 02 Sep 2009
Posts: 47157
Re: X is an integer?  [#permalink]

### Show Tags

04 Feb 2012, 12:10
1
1
boomtangboy wrote:
Is X an integer?

A] X/2 is an integer
B] 2X is an integer

I used a fraction (4/2) in A to prove that X is not an integer but OA is different

Is x an integer?

(1) x/2 is an integer. For x/2 to be an integer x must be an integer --> $$\frac{x}{2}=integer$$ --> $$x=2*integer=integer$$, as you can see $$x$$ is not only an integer but an even integer. Sufficient.

(2) 2x is an integer --> x may or may not be an integer, for instance $$x=0.5$$ or $$x=1$$. Basically $$x$$ is of a type $$\frac{integer}{2}$$, hence $$x$$ may be an integer itself or half of an integer 0.5, 1.5, ... Not sufficient.

As for your example: 4/2=2=integer, so 4/2 is just another way of writing integer 2, like 6/3 or 8/4. Also notice that any integer can be expressed as the ratio of 2 integers.

Hope it's clear.
_________________
Non-Human User
Joined: 09 Sep 2013
Posts: 7312
Re: Is x an integer?  [#permalink]

### Show Tags

15 Sep 2017, 07:33
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: Is x an integer? &nbs [#permalink] 15 Sep 2017, 07:33
Display posts from previous: Sort by

# Events & Promotions

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.