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

It is currently 20 Oct 2014, 13:45

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

If d is the standard deviation of x, y, and z, what is the

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Manager
Manager
avatar
Joined: 05 Jul 2006
Posts: 199
Followers: 1

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

If d is the standard deviation of x, y, and z, what is the [#permalink] New post 22 Aug 2006, 12:08
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 1 sessions
If d is the standard deviation of x, y, and z, what is the standard deviation of x+5, y+5 and z+5?

d
3d
15d
d+5
d+15
Director
Director
User avatar
Joined: 06 May 2006
Posts: 782
Followers: 3

Kudos [?]: 14 [0], given: 0

 [#permalink] New post 22 Aug 2006, 12:14
Hmmm - I think its A...

The difference of each of the values with their mean does not change, so the SD should not change as well...
Senior Manager
Senior Manager
avatar
Joined: 14 Jul 2005
Posts: 405
Followers: 1

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

 [#permalink] New post 22 Aug 2006, 12:21
d it is ! The answer should be A...

The difference between the mean and the actual numbers will remember the same.
Manager
Manager
avatar
Joined: 09 Jul 2006
Posts: 85
Location: India
Followers: 1

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

 [#permalink] New post 22 Aug 2006, 12:25
mean will change
new mean = (x+5+y+5+z+5)/3 = old mean + 5
but as each of the data points has moved ahead by 5 and even the mean has moved ahead by 5, the SD (which is nothing but a representation of relative distance b/w mean and each of the data points) will remain the same.
this can be shown mathematically as well.
Hence A.
_________________

Cheers!
Prashrash.

  [#permalink] 22 Aug 2006, 12:25
    Similar topics Author Replies Last post
Similar
Topics:
20 Experts publish their posts in the topic Is the standard deviation of the numbers X, Y and Z equal to fozzzy 11 17 Jan 2013, 05:15
2 Experts publish their posts in the topic If d is the standard deviation x, y, and z, what is the stan LM 5 10 May 2010, 08:37
2 If d is the standard deviation of x, y, and z , what is the alimad 3 20 Oct 2007, 08:59
1 Source: GMATPrep If d is the standard deviation of x, y Hang Tuah 1 21 Sep 2007, 20:46
14 Experts publish their posts in the topic If d is the standard deviation x, y, and z, what is the stan gmacvik 7 07 Oct 2006, 11:52
Display posts from previous: Sort by

If d is the standard deviation of x, y, and z, what is the

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

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 the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.