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

 It is currently 26 Apr 2015, 13:33

### 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

# standard deviation

 Question banks Downloads My Bookmarks Reviews Important topics
Author Message
TAGS:
Intern
Joined: 17 Dec 2006
Posts: 39
Followers: 0

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

standard deviation [#permalink]  08 Feb 2009, 01:10

if d is a standard deviation of x, y and z, what is the standard deviation of x+5, y+5 and z+5?
1) d
2) 3d
3) 15d
4) d+5
5) d+15

Senior Manager
Joined: 08 Jan 2009
Posts: 329
Followers: 2

Kudos [?]: 86 [1] , given: 5

Re: standard deviation [#permalink]  08 Feb 2009, 07:03
1
KUDOS
when each term in the series increases by the same amount,hence the mean also increase the same.The S.D does not change for the series.

Hence Ans : 1) d
Manager
Joined: 27 May 2008
Posts: 203
Followers: 1

Kudos [?]: 19 [1] , given: 0

Re: standard deviation [#permalink]  08 Feb 2009, 07:25
1
KUDOS
Zaur wrote:

if d is a standard deviation of x, y and z, what is the standard deviation of x+5, y+5 and z+5?
1) d
2) 3d
3) 15d
4) d+5
5) d+15

A

SD will not change if same number is added/sub from the given set of numbers...

Also, if the same number is multiplied/dvided from the given se of the number.. SD also have to be multiplied/dvided...
same case in percentage as well
SVP
Joined: 07 Nov 2007
Posts: 1828
Location: New York
Followers: 29

Kudos [?]: 535 [1] , given: 5

Re: standard deviation [#permalink]  08 Feb 2009, 16:49
1
KUDOS
agree with A..

standard deviation will not change if you shift values by same number.
_________________

Smiling wins more friends than frowning

Senior Manager
Joined: 02 Nov 2008
Posts: 283
Followers: 1

Kudos [?]: 42 [1] , given: 2

Re: standard deviation [#permalink]  08 Feb 2009, 16:56
1
KUDOS
Standard Deviation measures the difference between a set of numbers. If all the #'s are increased by the same amount (whether it's 5, 50, or 500) the standard deviation doesn't change.
So yes the answer is A.
Intern
Joined: 17 Dec 2006
Posts: 39
Followers: 0

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

Re: standard deviation [#permalink]  08 Feb 2009, 22:36
thanks a lot

brgds
Zaur
Re: standard deviation   [#permalink] 08 Feb 2009, 22:36
Similar topics Replies Last post
Similar
Topics:
Standard Deviation 1 18 Jul 2009, 23:35
Standard Deviation 1 17 Mar 2009, 01:47
1 Standard Deviation 11 10 Mar 2009, 05:03
Standard Deviation 2 05 Nov 2007, 05:45
Standard Deviation 5 12 Dec 2006, 03:38
Display posts from previous: Sort by

# standard deviation

 Question banks Downloads My Bookmarks Reviews Important topics

 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®.