Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 26 Apr 2015, 13:17

### 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

# DS = Modulus

Author Message
TAGS:
Director
Joined: 12 Oct 2008
Posts: 557
Followers: 2

Kudos [?]: 125 [0], given: 2

DS = Modulus [#permalink]  19 Sep 2009, 12:31
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 100% (00:22) wrong based on 0 sessions
what is the value of |x|

1. x = - |x|
2. x^2 = 4

[Reveal] Spoiler:
OA B IMO D
Intern
Joined: 20 Aug 2009
Posts: 11
Followers: 0

Kudos [?]: 1 [0], given: 11

Re: DS = Modulus [#permalink]  19 Sep 2009, 12:38
Answer would be B (2) alone is sufficient.

1. x = - |x| that means x < 0 ..insufficient..for example lets say x=-2 , then |x| = 2 so in order for the condition to match x has to be negative. this will not work for x = 2

2. x square = 4. i.e x= 2 or x = -2 but |x| = 2 ...sufficient..
Intern
Joined: 03 Sep 2009
Posts: 29
Followers: 0

Kudos [?]: 8 [0], given: 1

Re: DS = Modulus [#permalink]  19 Sep 2009, 12:42
Agree with your solution. Ans: B

keys wrote:
Answer would be B (2) alone is sufficient.

1. x = - |x| that means x < 0 ..insufficient..for example lets say x=-2 , then |x| = 2 so in order for the condition to match x has to be negative. this will not work for x = 2

2. x square = 4. i.e x= 2 or x = -2 but |x| = 2 ...sufficient..
Director
Joined: 12 Oct 2008
Posts: 557
Followers: 2

Kudos [?]: 125 [0], given: 2

Re: DS = Modulus [#permalink]  19 Sep 2009, 12:44
OA is B

my thinking is x = -|x|

|x| will always +ve it means x = -x only 0 can satisfy this condition, therefore x = 0

what is wrong here?

keys wrote:
Whats OA?
Intern
Joined: 03 Sep 2009
Posts: 29
Followers: 0

Kudos [?]: 8 [0], given: 1

Re: DS = Modulus [#permalink]  19 Sep 2009, 12:51
|x| >= 0 with all x
but |x| = x only with x >=0
so when you say "it means x = -x " you only think about x>=0 and you forgot the case x <0.
when x <0 => |x| = -x with all x <=0

OA is B

my thinking is x = -|x|

|x| will always +ve it means x = -x only 0 can satisfy this condition, therefore x = 0

what is wrong here?

keys wrote:
Whats OA?
Manager
Joined: 15 Sep 2009
Posts: 138
Followers: 1

Kudos [?]: 18 [0], given: 2

Re: DS = Modulus [#permalink]  20 Sep 2009, 03:32
statement 1 is insuff

statement 2 : x can be either 2 or -2. So |x| = 2.suff

I wud go with option 2
Re: DS = Modulus   [#permalink] 20 Sep 2009, 03:32
Similar topics Replies Last post
Similar
Topics:
DS inequalities and Modulus 3 02 Sep 2012, 02:52
MODULUS 3 14 Mar 2012, 17:45
DS-Modulus 2 05 Jul 2011, 01:46
Modulus 4 28 Oct 2009, 15:40
Modulus DS 3 14 Jul 2006, 14:45
Display posts from previous: Sort by