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

It is currently 25 Sep 2016, 07:38
GMAT Club Tests

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

A certain characteristic in a large population has a

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

3 KUDOS received
Manager
Manager
avatar
Joined: 02 Dec 2012
Posts: 178
Followers: 4

Kudos [?]: 1977 [3] , given: 0

A certain characteristic in a large population has a [#permalink]

Show Tags

New post 12 Dec 2012, 04:19
3
This post received
KUDOS
45
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

52% (02:04) correct 48% (01:24) wrong based on 978 sessions

HideShow timer Statistics

A certain characteristic in a large population has a distribution that is symmetric about the mean m. If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m + d ?

(A) 16%
(B) 32%
(C) 48%
(D) 84%
(E) 92%
[Reveal] Spoiler: OA
Expert Post
9 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 34820
Followers: 6477

Kudos [?]: 82576 [9] , given: 10108

Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 12 Dec 2012, 04:26
9
This post received
KUDOS
Expert's post
25
This post was
BOOKMARKED
Walkabout wrote:
A certain characteristic in a large population has a distribution that is symmetric about the mean m. If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m + d ?

(A) 16%
(B) 32%
(C) 48%
(D) 84%
(E) 92%


Given that 68% lies between m-d and m+d, thus 32% lies out of this range.

Now, since the distribution is symmetric about m, then half of the 32%, so 16%, lies to the right of m+d. Therefore, 16% lies to the right of m+d, and hence 84% lies to the left of m+d, which means that 84% is less than m+d.

Answer: D.

Similar questions to practice:
the-lifetime-of-all-the-batteries-produced-by-a-certain-comp-101472.html
70-75-80-85-90-105-105-130-130-130-the-list-shown-consist-of-100361.html
the-standard-deviation-of-a-normal-distribution-of-data-is-99221.html
for-a-certain-exam-a-score-of-58-was-2-standard-deviations-b-128661.html
given-that-the-mean-of-set-a-is-10-what-is-the-range-of-two-141964.html

Hope it helps.
_________________

New to the Math Forum?
Please read this: All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Intern
Intern
avatar
Joined: 09 Sep 2013
Posts: 19
Followers: 1

Kudos [?]: 1 [0], given: 7

Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 20 Oct 2013, 19:29
Not understanding this. Would someone be kind enough to provide a picture?

Thanks,
C
Expert Post
8 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 34820
Followers: 6477

Kudos [?]: 82576 [8] , given: 10108

Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 20 Oct 2013, 23:27
8
This post received
KUDOS
Expert's post
4
This post was
BOOKMARKED
Manager
Manager
User avatar
Joined: 12 Jan 2013
Posts: 244
Followers: 4

Kudos [?]: 59 [0], given: 47

GMAT ToolKit User
Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 13 Jan 2014, 02:28
Walkabout wrote:
A certain characteristic in a large population has a distribution that is symmetric about the mean m. If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m + d ?

(A) 16%
(B) 32%
(C) 48%
(D) 84%
(E) 92%



This is easiest to solve with a bell-curve histogram. m here is equal to µ in the Gaussian normal distribution and thus m = 50% of the total population.

So, if 68% is one st.Dev, then on either side of m we have 68/2 = 34%. So, 34% are to the right and left of m (= 50%). In other words, our value m + d = 50 + 34 = 84% going from the mean m, to the right of the distribution in the bell shaped histogram.. This means that 84% of the values are below m + d.

Like I said, doing it on a bell-curve histogram is much easier to fully "get" how this works, or you could apply GMAT percentile jargon/theory to it :-D
Senior Manager
Senior Manager
User avatar
Joined: 25 Sep 2012
Posts: 299
Location: India
Concentration: Strategy, Marketing
GMAT 1: 660 Q49 V31
GMAT 2: 680 Q48 V34
Followers: 2

Kudos [?]: 123 [0], given: 242

GMAT ToolKit User Reviews Badge
Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 01 Jun 2014, 05:18
Bunuel wrote:
runningguy wrote:
Not understanding this. Would someone be kind enough to provide a picture?

Thanks,
C


Check below:
Attachment:
Distribution.png
To understand better please follow the links provided in my post above.


-------16-------34-------m-------34-------16-------

We can't say that the 68% is divided equally on both the sides of m, can we?
I'm asking this, because that's how I solved it. However, I got it right...
Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 34820
Followers: 6477

Kudos [?]: 82576 [1] , given: 10108

Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 01 Jun 2014, 05:41
1
This post received
KUDOS
Expert's post
b2bt wrote:
Bunuel wrote:
runningguy wrote:
Not understanding this. Would someone be kind enough to provide a picture?

Thanks,
C


Check below:
Attachment:
Distribution.png
To understand better please follow the links provided in my post above.


-------16-------34-------m-------34-------16-------

We can't say that the 68% is divided equally on both the sides of m, can we?
I'm asking this, because that's how I solved it. However, I got it right...


You are not right. Check the diagram.

A distribution is symmetric about the mean m, implies that half of 68% is to the left of m and another half to the right of m.
_________________

New to the Math Forum?
Please read this: All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Senior Manager
Senior Manager
User avatar
Joined: 25 Sep 2012
Posts: 299
Location: India
Concentration: Strategy, Marketing
GMAT 1: 660 Q49 V31
GMAT 2: 680 Q48 V34
Followers: 2

Kudos [?]: 123 [0], given: 242

GMAT ToolKit User Reviews Badge
Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 01 Jun 2014, 06:24
Bunuel wrote:
b2bt wrote:
-------16-------34-------m-------34-------16-------

We can't say that the 68% is divided equally on both the sides of m, can we?
I'm asking this, because that's how I solved it. However, I got it right...


You are not right. Check the diagram.

A distribution is symmetric about the mean m, implies that half of 68% is to the left of m and another half to the right of m.


Basically my doubt is
68% = m + >m-d + <m+d
OR
68% = >m-d + <m+d (and not m)

I considered the 2nd eqn and after looking at the pic I understood it that it should as the 1st eqn. Just wanted to confirm that 1st eqn is right :)
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 34820
Followers: 6477

Kudos [?]: 82576 [0], given: 10108

Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 02 Jun 2014, 01:37
b2bt wrote:
Bunuel wrote:
b2bt wrote:
-------16-------34-------m-------34-------16-------

We can't say that the 68% is divided equally on both the sides of m, can we?
I'm asking this, because that's how I solved it. However, I got it right...


You are not right. Check the diagram.

A distribution is symmetric about the mean m, implies that half of 68% is to the left of m and another half to the right of m.


Basically my doubt is
68% = m + >m-d + <m+d
OR
68% = >m-d + <m+d (and not m)

I considered the 2nd eqn and after looking at the pic I understood it that it should as the 1st eqn. Just wanted to confirm that 1st eqn is right :)


I don't understand what you mean by either of the above equations.
_________________

New to the Math Forum?
Please read this: All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 11663
Followers: 527

Kudos [?]: 141 [0], given: 0

Premium Member
Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 10 Jun 2015, 05:54
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 Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 11663
Followers: 527

Kudos [?]: 141 [0], given: 0

Premium Member
Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 04 Jul 2016, 03:35
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 Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Intern
Intern
avatar
Joined: 24 Jun 2016
Posts: 4
Followers: 0

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

Statistics [#permalink]

Show Tags

New post 20 Jul 2016, 11:55
A certain characteristic in a large population has a distribution that is symmetric about the mean m. If 68% of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m+d?

A. 16%
B. 32%
C. 48%
D. 84%
E. 92%
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 34820
Followers: 6477

Kudos [?]: 82576 [0], given: 10108

Re: A certain characteristic in a large population has a [#permalink]

Show Tags

New post 20 Jul 2016, 12:08
Saayan wrote:
A certain characteristic in a large population has a distribution that is symmetric about the mean m. If 68% of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m+d?

A. 16%
B. 32%
C. 48%
D. 84%
E. 92%


Merging topics.

Please refer to the discussion above.

Also, please read carefully and follow: rules-for-posting-please-read-this-before-posting-133935.html Thank you.
_________________

New to the Math Forum?
Please read this: All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Director
Director
User avatar
Joined: 04 Jun 2016
Posts: 656
GMAT 1: 750 Q49 V43
Followers: 39

Kudos [?]: 139 [0], given: 36

A certain characteristic in a large population has a [#permalink]

Show Tags

New post 23 Jul 2016, 03:03
Walkabout wrote:
A certain characteristic in a large population has a distribution that is symmetric about the mean m. If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m + d ?

(A) 16%
(B) 32%
(C) 48%
(D) 84%
(E) 92%


Any large population has a characteristic graph known as the Normal distribution curve that looks like a bell.
SEE THE ATTACHED IMAGE
The unique property of Normal distribution is that 68% of samples lies with in the 1st SD. 95% of samples fall with in 2nd SD and about 99% of samples fall within the 3rd sd.
The Normal distraction curve is symmetric around the arithmetic mean and positive SD and negative SD are equidistant from the mean
Half of the samples lies on the left of the mean and half of the samples lies on the right on the mean.
The x axis has the following form
3SD...........2SD.........MEAN...........2SD............3SD
3d.............2d..........mean............d................3d
2%............14%<---------50%---------->84%..............99%
m+d=84%
therefore remaining samples = 100-84 = 16

ANSWER IS A

Image
_________________

Posting an answer without an explanation is "GOD COMPLEX". The world doesn't need any more gods. Please explain you answers properly.
FINAL GOODBYE :- 17th SEPTEMBER 2016.

A certain characteristic in a large population has a   [#permalink] 23 Jul 2016, 03:03
    Similar topics Author Replies Last post
Similar
Topics:
1 City X has a population 4 times as great as the population of City Y, AbdurRakib 2 14 Jun 2016, 14:48
2 Experts publish their posts in the topic A certain characteristic in a large population has a distribution that MathRevolution 3 30 Mar 2016, 00:27
1 Experts publish their posts in the topic If the population of a certain country increases at the rate Bunuel 10 09 Jun 2014, 06:45
24 Experts publish their posts in the topic A certain characteristic in a large population has a cipher 3 08 May 2010, 11:57
13 Experts publish their posts in the topic A certain characteristic in a large population has a vivektripathi 4 18 Sep 2008, 06:16
Display posts from previous: Sort by

A certain characteristic in a large population has a

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| 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®.