BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Standard Deviation Problem

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 96
Joined: Mon Mar 07, 2011 8:43 pm
Thanked: 1 times
Followed by:1 members

Standard Deviation Problem

by yvonne0923 » Fri May 06, 2011 12:00 pm
Is the standard deviation of Set A greater than the standard deviation of Set B?
(1) the range of A is greater than the range of B
(2) The sets have the same number of terms














_____________________________________________________________________________________________________
[spoiler]O.A: E[/spoiler]
My answer is B, since(1) definitely does not work, but (2)the sets have the same numbers of terms. Does it mean both sets have 7 terms(for example) or exactly same numbers?

Thanks,

[/spoiler]
Top
Source: — Data Sufficiency |
User avatar
Legendary Member
Posts: 582
Joined: Tue Mar 08, 2011 12:48 am
Thanked: 61 times
Followed by:6 members
GMAT Score:740

by force5 » Fri May 06, 2011 12:20 pm
i didnt like this question. what is the source?

well if i consider what you have written then i would answer E.

statement 1 talks about range which is insufficient to tell us about standard deviation.

statement 2 talks about same number of terms. it can have 2 terms each or 5 terms each. but we dont know the distribution. hence insufficient.

combining still insufficient

This doesnt make a good question. there has to be something missing in this question.
Top
User avatar
Senior | Next Rank: 100 Posts
Posts: 81
Joined: Sat Aug 08, 2009 1:16 pm
Thanked: 2 times

by Arcane66 » Fri May 06, 2011 6:45 pm
I got E too. I actually looked up standard deviation again and the basic formula for it. I know you can't tell from #1 or #2 alone. #1 doesn't tell you anything because all the terms in between the highest and lowest numbers could be disproportionately large or small. #2 by itself doesn't mean anything because we don't know the values. With both you still don't know because of the fact that you could have values skewed high or low.
Top
Post new topic Post Reply
• Page 1 of 1