GMAT Question of the Day: Daily via email | Daily via Instagram New to GMAT Club? Watch this Video

It is currently 05 Aug 2020, 09:08

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Is |k| = 2? (1) k^2 = 4 (2) k = |-2|

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Find Similar Topics 
Manager
Manager
User avatar
Joined: 27 Feb 2010
Posts: 70
Location: Denver
Is |k| = 2? (1) k^2 = 4 (2) k = |-2|  [#permalink]

Show Tags

New post 28 Apr 2010, 11:30
4
8
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

77% (00:34) correct 23% (00:41) wrong based on 448 sessions

HideShow timer Statistics

Is |k| = 2?

(1) k^2 = 4
(2) k = |-2|
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 65807
Is |k| = 2? (1) k^2 = 4 (2) k = |-2|  [#permalink]

Show Tags

New post 16 Oct 2013, 05:52
Math Revolution GMAT Instructor
User avatar
V
Joined: 16 Aug 2015
Posts: 9261
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Is |k| = 2? (1) k^2 = 4 (2) k = |-2|  [#permalink]

Show Tags

New post 31 Jan 2016, 21:13
Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution.

Is |k| = 2?

(1) k^2 = 4
(2) k = |-2|


In the original condition, there is 1 variable(k), which should match with the number of equations. So you need 1 equation.
For 1) 1 equation, for 2) 1 equation, which is likely to make D the answer.
For 1), k=-2,2 but |k|=|2|,|-2|=2, which is unique and sufficient.
For 2), k=|-2|=2, which is unique and sufficient.
Therefore, the answer is D.


 For cases where we need 1 more equation, such as original conditions with “1 variable”, or “2 variables and 1 equation”, or “3 variables and 2 equations”, we have 1 equation each in both 1) and 2). Therefore, there is 59 % chance that D is the answer, while A or B has 38% chance and C or E has 3% chance. Since D is most likely to be the answer using 1) and 2) separately according to DS definition. Obviously there may be cases where the answer is A, B, C or E.
_________________
MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only $79 for 1 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"
Director
Director
User avatar
D
Joined: 17 Mar 2014
Posts: 510
GMAT ToolKit User Reviews Badge
Is |k| = 2? (1) k^2 = 4 (2) k = |-2|  [#permalink]

Show Tags

New post 30 Dec 2018, 17:10
Bunuel wrote:

Is |k| = 2?

(1) k^2 = 4 --> |k| = 2. Sufficient.

(2) k = |-2| --> k=2 --> |k| = 2. Sufficient.

Answer: D.


Hello Bunuel,

I am not getting how option 2 is sufficient. As per question statement- \(|K| =2\) so K can 2 or -2

Option 2 says K= |-2| =2, it doesn't give option of -2.
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 65807
Re: Is |k| = 2? (1) k^2 = 4 (2) k = |-2|  [#permalink]

Show Tags

New post 31 Dec 2018, 00:55
ammuseeru wrote:
Bunuel wrote:
Is |k| = 2?[/b]

(1) k^2 = 4 --> |k| = 2. Sufficient.

(2) k = |-2| --> k=2 --> |k| = 2. Sufficient.

Answer: D.


Hello Bunuel,

I am not getting how option 2 is sufficient. As per question statement- \(|K| =2\) so K can 2 or -2

Option 2 says K= |-2| =2, it doesn't give option of -2.


The question asks: Is |k| = 2?

(2) says: k = 2. If k = 2, then |k| = 2.
_________________
Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 15598
Re: Is |k| = 2? (1) k^2 = 4 (2) k = |-2|  [#permalink]

Show Tags

New post 14 Jul 2020, 19:00
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.
_________________
GMAT Club Bot
Re: Is |k| = 2? (1) k^2 = 4 (2) k = |-2|   [#permalink] 14 Jul 2020, 19:00

Is |k| = 2? (1) k^2 = 4 (2) k = |-2|

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne