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

It is currently 14 Feb 2016, 05:31
GMAT Club Tests

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Standard deviation .. Conceptual and advanced one

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Manager
Manager
avatar
Joined: 25 Dec 2009
Posts: 99
Followers: 1

Kudos [?]: 99 [0], given: 3

Standard deviation .. Conceptual and advanced one [#permalink] New post 12 Jan 2010, 03:16
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

14% (00:00) correct 86% (00:47) wrong based on 27 sessions
Both the ranges of 2 lists are from 1 to 100, whose deviation is greater?
1) List 1 has three 100 and two 50; List 2 has two 100 and three 50.
2) The averages are the same.

One alone can not help : We can have list of numbers in any fashion as only range has to be within limit of 100 . not sufficent

Obviously two alone is not adequate to answer the question a well . If mean are same , does not mean anything for SD unless you know the variation of its elemnt from the mean. not sufficient.

Is it possible to answer if one and two are together ? Answers with explanations only please.
Expert Post
Verbal Forum Moderator
Verbal Forum Moderator
User avatar
Joined: 02 Aug 2009
Posts: 2072
Followers: 83

Kudos [?]: 973 [0], given: 37

Re: Standard deviation .. Conceptual and advanced one [#permalink] New post 12 Jan 2010, 04:11
Expert's post
hi , isnt SI suff.. its giving you the elements in each, if i have understood the SI properly........
_________________

BACK IN CLUB AFTER A GAP OF 6 YEARS

http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
Errors in CR ---- http://gmatclub.com/forum/gmat-institutes-please-review-the-following-qs-211573.html

Tuck Thread Master
User avatar
Joined: 20 Aug 2009
Posts: 312
Location: Tbilisi, Georgia
Schools: Stanford (in), Tuck (WL), Wharton (ding), Cornell (in)
Followers: 15

Kudos [?]: 118 [0], given: 69

Re: Standard deviation .. Conceptual and advanced one [#permalink] New post 12 Jan 2010, 04:38
Statement 2 is insufficient.

I do not understand Statement 1 though: Does it give complete enumeration of numbers in lists? OR it only mentions some numbers that are in lists? (albeit here could be other numbers we know nothing about)
Intern
Intern
avatar
Joined: 20 Dec 2009
Posts: 14
Followers: 1

Kudos [?]: 23 [0], given: 5

Re: Standard deviation .. Conceptual and advanced one [#permalink] New post 13 Jan 2010, 02:36
Hi,
Both the statements are individually as well as together are insufficient to answer the question.

For Standard Deviation we need to know the mean and the numbers in the distribution. Here, without the numbers in distribution we are unable to determine the mean and deviation from the mean.

Thanks!
Senior Manager
Senior Manager
User avatar
Joined: 21 Jul 2009
Posts: 366
Schools: LBS, INSEAD, IMD, ISB - Anything with just 1 yr program.
Followers: 16

Kudos [?]: 130 [0], given: 22

Re: Standard deviation .. Conceptual and advanced one [#permalink] New post 13 Jan 2010, 06:45
I would rather say, to know the SD of a set/list, we need to know the mean, the elements and the "number of elements" specifically as well. We only have the range information, which does not help us know anything about the total number of elements in each list given. The occurrence of a specific element in a list can become irrelevant depending on the number of elements.

My answer is E.
_________________

I am AWESOME and it's gonna be LEGENDARY!!!

Senior Manager
Senior Manager
avatar
Joined: 01 Feb 2010
Posts: 267
Followers: 1

Kudos [?]: 47 [0], given: 2

Re: Standard deviation .. Conceptual and advanced one [#permalink] New post 12 Feb 2010, 23:30
GMATMadeeasy wrote:
Both the ranges of 2 lists are from 1 to 100, whose deviation is greater?
1) List 1 has three 100 and two 50; List 2 has two 100 and three 50.
2) The averages are the same.

One alone can not help : We can have list of numbers in any fashion as only range has to be within limit of 100 . not sufficent

Obviously two alone is not adequate to answer the question a well . If mean are same , does not mean anything for SD unless you know the variation of its elemnt from the mean. not sufficient.

Is it possible to answer if one and two are together ? Answers with explanations only please.


Statement 1 & 2 alone cannot solve.
To find SD we need to know how far each element is from mean.
Even taking both together, if average is same for both sets we do not know the difference of each element from mean
henceforth cannot solve this problem with both statements even so E.
Expert Post
GMAT Tutor
avatar
Joined: 24 Jun 2008
Posts: 1180
Followers: 353

Kudos [?]: 1125 [0], given: 4

CAT Tests
Re: Standard deviation .. Conceptual and advanced one [#permalink] New post 06 Oct 2010, 10:30
Expert's post
GMATMadeeasy wrote:
Both the ranges of 2 lists are from 1 to 100, whose deviation is greater?
1) List 1 has three 100 and two 50; List 2 has two 100 and three 50.
2) The averages are the same.

One alone can not help : We can have list of numbers in any fashion as only range has to be within limit of 100 . not sufficent

Obviously two alone is not adequate to answer the question a well . If mean are same , does not mean anything for SD unless you know the variation of its elemnt from the mean. not sufficient.

Is it possible to answer if one and two are together ? Answers with explanations only please.


The wording of this question is terrible - where is it from? The 'range' of a set is a single number, the difference of the largest and smallest elements. We don't say that 'the range is from 1 to 100'; that's misusing terminology. The term 'deviation' in statistics is also not interchangeable with 'standard deviation'; the 'deviation' of an element x is the difference between x and the mean. It's meaningless to talk about the deviation of a list. I'm sure the question means to discuss standard deviation instead. If so, the answer is certainly E; we have almost no information about how the elements in the lists are distributed.
_________________

GMAT Tutor in Toronto

If you are looking for online GMAT math tutoring, or if you are interested in buying my advanced Quant books and problem sets, please contact me at ianstewartgmat at gmail.com

VP
VP
avatar
Status: There is always something new !!
Affiliations: PMI,QAI Global,eXampleCG
Joined: 08 May 2009
Posts: 1354
Followers: 15

Kudos [?]: 192 [0], given: 10

Re: Standard deviation .. Conceptual and advanced one [#permalink] New post 19 May 2011, 00:13
ranges are 1-100 means we can't fix values.

E
_________________

Visit -- http://www.sustainable-sphere.com/
Promote Green Business,Sustainable Living and Green Earth !!

BSchool Thread Master
User avatar
Status: Tutor
Joined: 05 Apr 2011
Posts: 542
Location: India
Concentration: Finance, Marketing
Schools: XLRI (A)
GMAT 1: 570 Q49 V19
GMAT 2: 700 Q51 V31
GPA: 3
WE: Information Technology (Computer Software)
Followers: 84

Kudos [?]: 419 [0], given: 49

Top 10 in overall
Re: Standard deviation .. Conceptual and advanced one [#permalink] New post 21 Nov 2015, 07:56
Please move this to DS
Thank you
GMATMadeeasy wrote:
Both the ranges of 2 lists are from 1 to 100, whose deviation is greater?
1) List 1 has three 100 and two 50; List 2 has two 100 and three 50.
2) The averages are the same.

One alone can not help : We can have list of numbers in any fashion as only range has to be within limit of 100 . not sufficent

Obviously two alone is not adequate to answer the question a well . If mean are same , does not mean anything for SD unless you know the variation of its elemnt from the mean. not sufficient.

Is it possible to answer if one and two are together ? Answers with explanations only please.

_________________

Ankit
You must Believe

GMAT Quant Tutor
How to start GMAT preparations?
How to Improve Quant Score?
Gmatclub Topic Tags
Check out my GMAT debrief

How to Solve :
Statistics || Reflection of a line || Remainder Problems || Inequalities

Re: Standard deviation .. Conceptual and advanced one   [#permalink] 21 Nov 2015, 07:56
Display posts from previous: Sort by

Standard deviation .. Conceptual and advanced one

  Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

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®.