NEW HERE? LEARN MORE
closeclose
Last visit was: 25 Apr 2024, 13:03 It is currently 25 Apr 2024, 13:03
Decision Tracker
My Rewards
New posts
New comers' posts

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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

Set X and set Y have 10 numbers each. Is standard deviation of set X

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
avatar
B
hkotadiya
Intern
Intern
Joined: 30 Aug 2017
Posts: 7
Own Kudos [?]: 89 [12]
Given Kudos: 17
Send PM
Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink] New post   05 Oct 2017, 07:40
2
Kudos
10
Bookmarks
00:00
A
B
C
D
E

Difficulty:

45% (medium)

Question Stats:

55% (01:06) correct 45% (00:57) wrong based on 237 sessions
Hide Show timer Statistics
Set X and set Y have 10 numbers each. Is standard deviation of set X greater than that of set Y ?
1) Range of set X is greater than that of set Y
2) Median of set X is greater than that of set Y
ShowHide Answer
Official Answer
E
Most Helpful Reply
User avatar
L
saswata4s
Current Student
Joined: 28 May 2014
Posts: 425
Own Kudos [?]: 1084 [9]
Given Kudos: 103
GMAT 1: 730 Q49 V41
Send PM
GMAT ToolKit User
Re: Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink] New post   05 Oct 2017, 08:22
7
Bookmarks
(1) Range can be much larger if there is one or two outliers numbers in a set. But SD is not necessarily has to be bigger. Insuff.

(2) consider the two sets:
set Y = 10, 10, 20, 30, 30
Set X = 20, 20, 30, 40, 40

The SD is same though the median of set X is bigger.

again,
set Y = 10, 10, 20, 30, 30
Set X = 29, 29, 30, 31, 31

The SD is smaller in set X though the median of set X is bigger. Hence, Insuff.

(1) & (2) together also Insuff.
Ans: E.
General Discussion
avatar
B
AC07
Intern
Intern
Joined: 29 Aug 2017
Posts: 30
Own Kudos [?]: 35 [1]
Given Kudos: 57
Send PM
Re: Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink] New post   07 Oct 2017, 23:18
1
Bookmarks
Harikrushna Kotadiya wrote:
Set X and set Y have 10 numbers each. Is standard deviation of set X greater than that of set Y ?
1) Range of set X is greater than that of set Y
2) Median of set X is greater than that of set Y



Set X and Set Y have 10 numbers each. Is SD of X > SD of Y?

Statement 1:
This statement is not sufficient because for set X, even though the smallest number and largest number maybe farther than in set Y, the rest of the numbers may be closely cluttered than in set Y.

Statement 2:
Standard deviation does not depend on the actual values of the numbers but the spread of the numbers from the average. Therefore, this statement is not sufficient.

Combining statements 1 and 2 is also not sufficient because it does not give any useful information about the spread of the numbers from the average.

Therefore, answer is E.
avatar
B
AC07
Intern
Intern
Joined: 29 Aug 2017
Posts: 30
Own Kudos [?]: 35 [1]
Given Kudos: 57
Send PM
Re: Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink] New post   07 Oct 2017, 23:19
1
Kudos
Harikrushna Kotadiya wrote:
Set X and set Y have 10 numbers each. Is standard deviation of set X greater than that of set Y ?
1) Range of set X is greater than that of set Y
2) Median of set X is greater than that of set Y



Set X and Set Y have 10 numbers each. Is SD of X > SD of Y?

Statement 1:
This statement is not sufficient because for set X, even though the smallest number and largest number maybe farther than in set Y, the rest of the numbers may be closely cluttered than in set Y.

Statement 2:
Standard deviation does not depend on the actual values of the numbers but the spread of the numbers from the average. Therefore, this statement is not sufficient.

Combining statements 1 and 2 is also not sufficient because it does not give any useful information about the spread of the numbers from the average.

Therefore, answer is E.
User avatar
G
DhruvS
Intern
Intern
Joined: 09 May 2018
Posts: 41
Own Kudos [?]: 81 [1]
Given Kudos: 121
Location: India
Send PM
Re: Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink] New post   14 Jun 2019, 23:03
1
Kudos
Can anyone please give a more detailed explanation for this Question?

Posted from my mobile device
avatar
B
utkarsh0892
Intern
Intern
Joined: 03 Jan 2020
Posts: 5
Own Kudos [?]: 1 [1]
Given Kudos: 14
Send PM
Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink] New post   31 May 2020, 02:35
1
Kudos
MansiRastogi1234 wrote:
What if the option had a) mean of set x is greater than that of set y ,would this option be sufficient ?

Posted from my mobile device

Yes it would still be insufficient.
S.D. depends more on dispersion of value around mean than on mean alone
Example:
X:10,20,30,40,50
Y:10,15,20,25,30
MeanX>MeanY
SDx>SDy

X:28,29,30,31,32
Y:10,15,20,25,30
MeanX>MeanY
SDx<SDy

Hope this would suffice .
User avatar
D
GMATGuruNY
Tutor
Joined: 04 Aug 2010
Posts: 1315
Own Kudos [?]: 3136 [1]
Given Kudos: 9
Schools:Dartmouth College
Send PM
Re: Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink] New post   31 Dec 2020, 10:10
1
Bookmarks
Expert Reply
Harikrushna Kotadiya wrote:
Set X and set Y have 10 numbers each. Is standard deviation of set X greater than that of set Y ?
1) Range of set X is greater than that of set Y
2) Median of set X is greater than that of set Y


For the purposes of the GMAT, standard deviation = average distance from the mean.
The two statements combined tell us nothing about the average distance from the mean and thus are INSUFFICIENT.

Show Spoiler
E
avatar
B
MansiRastogi1234
Intern
Intern
Joined: 06 Jun 2019
Posts: 1
Own Kudos [?]: 0 [0]
Given Kudos: 4
Send PM
Re: Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink] New post   17 Sep 2019, 00:54
What if the option had a) mean of set x is greater than that of set y ,would this option be sufficient ?

Posted from my mobile device
User avatar
P
MHIKER
Director
Director
Joined: 14 Jul 2010
Status:No dream is too large, no dreamer is too small
Posts: 972
Own Kudos [?]: 4928 [0]
Given Kudos: 690
Concentration: Accounting
Send PM
Re: Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink] New post   31 Dec 2020, 07:55
Top Contributor
Harikrushna Kotadiya wrote:
Set X and set Y have 10 numbers each. Is standard deviation of set X greater than that of set Y?
1) Range of set X is greater than that of set Y
2) Median of set X is greater than that of set Y


(1) Range can't be an indicator for standard deviation measurement. The greater or lower range of two sets can give irregular standard deviation.

Set X ={1,2,3,4,5,6,8,9}; The range is 8, standard deviation 1

Set Y = {2, 4,5,9}; The range is 7, the standard deviation will be greater than set X.

OR, Set Y_2= {30, 30.5, 30.6}; The range is 0.6, the standard deviation will be less than set X.

Insufficient.

(2) The above two examples also showed greater median can't confirm the magnitude of Standard Deviation. Insufficient.

Considering both:
Again the above examples showed irregular standard deviation. Insufficient.

The answer is E.
User avatar
bumpbot
Non-Human User
Joined: 09 Sep 2013
Posts: 32678
Own Kudos [?]: 822 [0]
Given Kudos: 0
Send PM
Re: Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink] New post   19 May 2023, 22:12
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
gmatclubot
Re: Set X and set Y have 10 numbers each. Is standard deviation of set X [#permalink]
19 May 2023, 22:12
Moderator:
Bunuel
Math Expert
92914 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions