GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 22 Mar 2019, 15:31

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.

Close

Request Expert Reply

Confirm Cancel

Set S consists of integers 7, 8, 10, 12, and 13. If integer n is inclu

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

Hide Tags

 
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 53792
Set S consists of integers 7, 8, 10, 12, and 13. If integer n is inclu  [#permalink]

Show Tags

New post 08 Oct 2014, 14:13
1
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

80% (01:20) correct 20% (01:38) wrong based on 100 sessions

HideShow timer Statistics

Tough and Tricky questions: Statistics



Set S consists of integers 7, 8, 10, 12, and 13. If integer n is included in the set, the average (arithmetic mean) of set S will increase by 20%. What is the value of integer n?

A. 10
B. 12
C. 16
D. 22
E. 24

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | 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: 23 Aug 2014
Posts: 8
Re: Set S consists of integers 7, 8, 10, 12, and 13. If integer n is inclu  [#permalink]

Show Tags

New post 08 Oct 2014, 16:13
Not sure how it is tricky !!!

Quite a simple one.

Current Avg = (7+8+10+12+13)/5 = 50/5 =10

So, New Avg = 1.2 * Current Avg = 12

12 = (50+n)/6

n= 72-50 =22 Ans
Director
Director
User avatar
Joined: 25 Apr 2012
Posts: 680
Location: India
GPA: 3.21
WE: Business Development (Other)
Premium Member Reviews Badge
Re: Set S consists of integers 7, 8, 10, 12, and 13. If integer n is inclu  [#permalink]

Show Tags

New post 08 Oct 2014, 20:31
1
Bunuel wrote:

Tough and Tricky questions: Statistics



Set S consists of integers 7, 8, 10, 12, and 13. If integer n is included in the set, the average (arithmetic mean) of set S will increase by 20%. What is the value of integer n?

A. 10
B. 12
C. 16
D. 22
E. 24


The average of given nos is 10 and we need to increase it by 20% so new average will be 12..
If the average of 6 nos (including n) is 12 then sum is 72
and sum of 5 no (excluding n) is 50

The number n to be added is 72-50=22
Ans D
_________________


“If you can't fly then run, if you can't run then walk, if you can't walk then crawl, but whatever you do you have to keep moving forward.”

SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1817
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: Set S consists of integers 7, 8, 10, 12, and 13. If integer n is inclu  [#permalink]

Show Tags

New post 08 Oct 2014, 21:36
1
Average of the given numbers \(= \frac{7 + 8 + 10 + 12 + 13}{5} = 10\)

Increment is 20% after including "n" = 10 + 2 = 12

New equation\(= \frac{50 + n}{6} = 12\)

n = 72 - 50 = 22

Answer = D
_________________

Kindly press "+1 Kudos" to appreciate :)

Target Test Prep Representative
User avatar
P
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 5409
Location: United States (CA)
Re: Set S consists of integers 7, 8, 10, 12, and 13. If integer n is inclu  [#permalink]

Show Tags

New post 22 Feb 2019, 16:36
Bunuel wrote:

Tough and Tricky questions: Statistics



Set S consists of integers 7, 8, 10, 12, and 13. If integer n is included in the set, the average (arithmetic mean) of set S will increase by 20%. What is the value of integer n?

A. 10
B. 12
C. 16
D. 22
E. 24



The average of the original set is 50/5 = 10. When n is added to the set, we have:

(50 + n)/6 = 1.2 x 10

50 + n = 6 x 12

50 + n = 72

n = 22

Answer: D
_________________

Scott Woodbury-Stewart

Founder and CEO

Scott@TargetTestPrep.com
TTP - Target Test Prep Logo
122 Reviews

5-star rated online GMAT quant
self study course

See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews

GMAT Club Bot
Re: Set S consists of integers 7, 8, 10, 12, and 13. If integer n is inclu   [#permalink] 22 Feb 2019, 16:36
Display posts from previous: Sort by

Set S consists of integers 7, 8, 10, 12, and 13. If integer n is inclu

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


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.