It is currently 23 Oct 2017, 19:34

### 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

# What is the standard deviation of set S ? 1. Set S consists

Author Message
VP
Joined: 22 Nov 2007
Posts: 1079

Kudos [?]: 681 [0], given: 0

What is the standard deviation of set S ? 1. Set S consists [#permalink]

### Show Tags

17 Feb 2008, 06:41
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

What is the standard deviation of set S ?
1. Set S consists of 10 even integers
2. The range of set S is 18

Kudos [?]: 681 [0], given: 0

Manager
Joined: 02 Jan 2008
Posts: 157

Kudos [?]: 132 [0], given: 0

### Show Tags

17 Feb 2008, 07:09
E

--
A: INSUFF (what even integers?)
B: INSUFF (Range tells 18, but other numbers are not known)

A & B: INSUFF (10 even integers with range 18 but they may not be consecutives and there can be repetitions)

Kudos [?]: 132 [0], given: 0

VP
Joined: 22 Nov 2007
Posts: 1079

Kudos [?]: 681 [0], given: 0

### Show Tags

21 Feb 2008, 23:59
srp wrote:
E

--
A: INSUFF (what even integers?)
B: INSUFF (Range tells 18, but other numbers are not known)

A & B: INSUFF (10 even integers with range 18 but they may not be consecutives and there can be repetitions)

if the question were to be: distinct even integers?

Kudos [?]: 681 [0], given: 0

Director
Joined: 14 Sep 2007
Posts: 908

Kudos [?]: 95 [0], given: 15

Schools: Kellogg '10

### Show Tags

22 Feb 2008, 15:51
marcodonzelli wrote:
srp wrote:
E

--
A: INSUFF (what even integers?)
B: INSUFF (Range tells 18, but other numbers are not known)

A & B: INSUFF (10 even integers with range 18 but they may not be consecutives and there can be repetitions)

if the question were to be: distinct even integers?

Probably be C then, since it would be st dev of any range of 18 consecutive even integers, which I think always be equal.
_________________

http://www.fantasticcontraption.com

GMAT Club Premium Membership - big benefits and savings

Kudos [?]: 95 [0], given: 15

Director
Joined: 14 Jan 2007
Posts: 775

Kudos [?]: 175 [0], given: 0

### Show Tags

23 Feb 2008, 09:59
rca215 wrote:
marcodonzelli wrote:
srp wrote:
E

--
A: INSUFF (what even integers?)
B: INSUFF (Range tells 18, but other numbers are not known)

A & B: INSUFF (10 even integers with range 18 but they may not be consecutives and there can be repetitions)

if the question were to be: distinct even integers?

Probably be C then, since it would be st dev of any range of 18 consecutive even integers, which I think always be equal.

St. dev is the spread around the mean.
If all even integers are distinct, they will spread in the same pattern around the mean.
In that case answer would be 'C'.

Kudos [?]: 175 [0], given: 0

SVP
Joined: 29 Aug 2007
Posts: 2472

Kudos [?]: 845 [0], given: 19

### Show Tags

23 Feb 2008, 10:18
rca215 wrote:
marcodonzelli wrote:
srp wrote:
E

--
A: INSUFF (what even integers?)
B: INSUFF (Range tells 18, but other numbers are not known)

A & B: INSUFF (10 even integers with range 18 but they may not be consecutives and there can be repetitions)

if the question were to be: distinct even integers?

Probably be C then, since it would be st dev of any range of 18 consecutive even integers, which I think always be equal.

it could be distinct integers with a range of 18 or some distinct and some repetitive integers with the same range. for ex:

a: 2, 4, 6, 8, 10, 12, 14, 16, 18, and 20
b: 2, 2, 6, 8, 10, 12, 14, 16, 18, and 20

in above cases, a and b have different Standard Deviations but fulfill both requirements in st. 1 and 2.

so only E makes sense.
_________________

Gmat: http://gmatclub.com/forum/everything-you-need-to-prepare-for-the-gmat-revised-77983.html

GT

Kudos [?]: 845 [0], given: 19

Manager
Joined: 05 Feb 2007
Posts: 139

Kudos [?]: 8 [0], given: 7

### Show Tags

06 Apr 2008, 18:01
i have a love/hate relationship with these types of questions.

I saw even integers and read "consecutive even integers".

Great question!

Kudos [?]: 8 [0], given: 7

Re: Tricky statistics   [#permalink] 06 Apr 2008, 18:01
Display posts from previous: Sort by