It is currently 13 Dec 2017, 01:34

### 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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# What inequality represents the condition 1<x<9

Author Message
TAGS:

### Hide Tags

Manager
Joined: 25 Aug 2011
Posts: 197

Kudos [?]: 387 [0], given: 11

Location: India
GMAT 1: 730 Q49 V40
WE: Operations (Insurance)
What inequality represents the condition 1<x<9 [#permalink]

### Show Tags

21 Oct 2011, 05:06
3
This post was
BOOKMARKED
00:00

Difficulty:

5% (low)

Question Stats:

85% (00:35) correct 15% (00:36) wrong based on 261 sessions

### HideShow timer Statistics

What inequality represents the condition 1<x<9?

(A) |x|<3
(B) |x+5|<4
(C) |x-1|<9
(D) |-5+x|<4
(E) |3+x|<5

OPEN DISCUSSION OF THE QUESTION IS HERE: which-of-the-following-represents-1-x-126845.html

TOPIC LOCKED. MODERATOR.

[Reveal] Spoiler: Doubt
The answer to this question is D.
I am confused because even C seems to be satisfying most of the numbers tested on this inequality . The answer is an obvious D, if we solve the algebraic inequality but on testing with numbers both options seem to be right
Am just trying to find a way to use the number plugging method accurately

Any body any idea ? Thanks ..
[Reveal] Spoiler: OA

Last edited by Bunuel on 03 Mar 2012, 00:41, edited 2 times in total.
Topic is locked

Kudos [?]: 387 [0], given: 11

Math Forum Moderator
Joined: 20 Dec 2010
Posts: 1949

Kudos [?]: 2136 [1], given: 376

Re: What inequality represents the condition 1<x<9 [#permalink]

### Show Tags

21 Oct 2011, 05:15
1
KUDOS
1
This post was
BOOKMARKED
devinawilliam83 wrote:
What inequality represents the condition 1<x<9?

(A) |x|<3
(B) |x+5|<4
(C) |x-1|<9
(D) |-5+x|<4
(E) |3+x|<5

Remember this:

|x|<k means; -k<x<+k

So,
D) |-5+x|<4
|x-5|<4
-4<x-5<4
-4+5<x-5+5<4+5
1<x<9

Ans: "D"

Please do the same for C.
_________________

Kudos [?]: 2136 [1], given: 376

Manager
Joined: 28 Sep 2011
Posts: 52

Kudos [?]: 14 [0], given: 9

Re: What inequality represents the condition 1<x<9 [#permalink]

### Show Tags

21 Oct 2011, 08:18
Quote:
I am confused because even C seems to be satisfying most of the numbers tested on this inequality . The answer is an obvious D, if we solve the algebraic inequality but on testing with numbers both options seem to be right
Am just trying to find a way to use the number plugging method accurately

Any body any idea ? Thanks ..

You need to test both numbers inside and outside the range of 1<x<9 to see if each inequality represents the condition of 1<x<9 and nothing more. The inequality found in answer C satisfies the range 1<x<9 but also includes numbers outside of this range.

You likely only tested numbers inside this range, which resulted in your error.

Kudos [?]: 14 [0], given: 9

Intern
Joined: 31 Jan 2012
Posts: 6

Kudos [?]: 5 [0], given: 0

Concentration: Finance, Economics
GPA: 2.98
Re: What inequality represents the condition 1<x<9 [#permalink]

### Show Tags

03 Mar 2012, 00:27
I honestly just do not understand. I read everyone's reply. But I still don't understand how this makes since. I read where you said outside the range but the way I am understanding it, the answer D doesn't work either. I am just lost. If anyone can explain this more in depth please do. I apologize for being difficult. It's hard for me to understand things like this without someone being right here with me to explain why and how you get the answer.

Kudos [?]: 5 [0], given: 0

Math Expert
Joined: 02 Sep 2009
Posts: 42577

Kudos [?]: 135443 [0], given: 12695

Re: What inequality represents the condition 1<x<9 [#permalink]

### Show Tags

03 Mar 2012, 00:38
Mercury14 wrote:
I honestly just do not understand. I read everyone's reply. But I still don't understand how this makes since. I read where you said outside the range but the way I am understanding it, the answer D doesn't work either. I am just lost. If anyone can explain this more in depth please do. I apologize for being difficult. It's hard for me to understand things like this without someone being right here with me to explain why and how you get the answer.

Here is another topic discussing the same question: which-of-the-following-represents-1-x-126845.html There is conceptual approach in Mike's post and plug-in method in my post.

Hope it helps.

_________________

Kudos [?]: 135443 [0], given: 12695

Re: What inequality represents the condition 1<x<9   [#permalink] 03 Mar 2012, 00:38
Display posts from previous: Sort by