It is currently Wed May 23, 2012 6:57 pm




   Post new topic Reply to topic      [ 3 posts ]  Bookmark and Share Oldest Best Reply
Author Message
  DS Q There is set of consecutive even integers. What is S.D? [#permalink]
New postPosted: Tue Jan 31, 2012 2:28 am 
Offline
Manager
Manager

Joined: Sat Sep 17, 2011
Posts: 223
Followers: 0

Kudos (?): 6 (0), given: 8

GMAT Tests User
There is a set of consecutive even integers. What is the Standard deviation of the set ?
1)There are 39 elements in the set.
2)The mean of the set is 382.

The answer to this question is A. Can someone explain the logic behind this ?

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


  Profile  
 
  Re: DS Q There is set of consecutive even integers. What is S.D? [#permalink]
New postPosted: Tue Jan 31, 2012 3:10 am 
Offline
Senior Manager
Senior Manager
User avatar

Status: May The Force Be With Me (D-DAY 15 May 2012)
Joined: Fri Jan 06, 2012
Posts: 311
Location: India
Followers: 1

Kudos (?): 26 (1), given: 16

Hi

In order to solve this problem we need to know the mean & the terms of the sample.

Statement A :
Gives us 39 consecutive even elements
Eg : 0,2,4,.....
To Compute SD
1. Compute the difference of each data point from the mean, and square the result of each
2. compute the average of these values, and take the square root

Which we can calculate easily from the given data

Thus statement A is sufficient

Statement B
Mean is 382 only gives us the mid point of the set but not the number of elements hence we cannot calculate the SD

Thus statement B is insufficient

Hope this helps

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


  Profile  
 
  Re: DS Q There is set of consecutive even integers. What is S.D? [#permalink]
New postPosted: Tue Jan 31, 2012 8:19 am 
Offline
Manager
Manager

Joined: Sat Sep 17, 2011
Posts: 223
Followers: 0

Kudos (?): 6 (0), given: 8

GMAT Tests User
Thanks man

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


  Profile  
 
Online
gmatclubot
Display posts from previous:  Sort by  

Post new topic Reply to topic  [ 3 posts ] 

 Similar topics   Author   Replies   Views   Last post 
DS - What is the median of the set of consecutive integers

in GMAT Data Sufficiency (DS)

xALIx

3

672

Mon Jul 14, 2008 5:28 pm

DS: Sets of Consecutive Integers

in GMAT Data Sufficiency (DS)

kevincan

7

298

Sun Aug 27, 2006 7:38 am

q, r, and s are consecutive even integers

in GMAT Problem Solving (PS)

Yalephd

6

496

Fri May 06, 2011 5:13 pm

DS # 12: Consecutive integers / odd or even

in GMAT Data Sufficiency (DS)

cpcalanoc

2

190

Sun Dec 19, 2004 7:05 pm

If q, r, and s are consecutive even integers and q < r

in GMAT Problem Solving (PS)

SimaQ

6

179

Mon Oct 02, 2006 11:53 pm





Who is online

Users browsing this forum: Google Adsense [Bot] and 0 guests


Search for:
Jump to:





[ Mobile Version ] GMAT Club MBA Forum Home | About | Privacy Policy | Terms and Conditions | GMAT Club Rules | Contact | Sitemap
Powered by phpBB © phpBB Group and phpBB SEO
Kindly note that GMAT (C) is a registered trademark of the Graduate Management Admission Council, and this site has neither been reviewed nor endorsed by GMAC.