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

It is currently 24 Jan 2019, 00:47

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
Events & Promotions in January
PrevNext
SuMoTuWeThFrSa
303112345
6789101112
13141516171819
20212223242526
272829303112
Open Detailed Calendar
  • Key Strategies to Master GMAT SC

     January 26, 2019

     January 26, 2019

     07:00 AM PST

     09:00 AM PST

    Attend this webinar to learn how to leverage Meaning and Logic to solve the most challenging Sentence Correction Questions.
  • Free GMAT Number Properties Webinar

     January 27, 2019

     January 27, 2019

     07:00 AM PST

     09:00 AM PST

    Attend this webinar to learn a structured approach to solve 700+ Number Properties question in less than 2 minutes.

which of the five numbers is multiplied by 3?

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

Hide Tags

 
VP
VP
User avatar
P
Joined: 31 Oct 2013
Posts: 1014
Concentration: Accounting, Finance
GPA: 3.68
WE: Analyst (Accounting)
which of the five numbers is multiplied by 3?  [#permalink]

Show Tags

New post 24 Jan 2018, 01:52
1
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

71% (01:58) correct 29% (01:45) wrong based on 21 sessions

HideShow timer Statistics

The average of the five members is 7. if one of the members is multiplied by 3, the average of the numbers increases to 9.4. which of the five numbers is multiplied by 3?

a)4
b)5
c)5.6
d)6
e) none of these
Senior Manager
Senior Manager
User avatar
G
Joined: 17 Oct 2016
Posts: 318
Location: India
Concentration: Operations, Strategy
GPA: 3.73
WE: Design (Real Estate)
GMAT ToolKit User Premium Member
Re: which of the five numbers is multiplied by 3?  [#permalink]

Show Tags

New post 24 Jan 2018, 02:19
1
Let say the unknown digit be x and the sum of the remaining four digits be y.

Now (x+y)/5=7 ie y=35-x

Also (3x+y)/5=9.4 ie y=47-3x

Solving for x, the multiplied number is 6. Option D

Posted from my mobile device
_________________

Help with kudos if u found the post useful. Thanks

Math Expert
User avatar
V
Joined: 02 Aug 2009
Posts: 7215
Re: which of the five numbers is multiplied by 3?  [#permalink]

Show Tags

New post 24 Jan 2018, 03:16
selim wrote:
The average of the five members is 7. if one of the members is multiplied by 3, the average of the numbers increases to 9.4. which of the five numbers is multiplied by 3?

a)4
b)5
c)5.6
d)6
e) none of these


hi

initial sum = 7*5=35
sum after a number is increased 3 times = 9.4*5=47
Increase = 47-35=12..

IMPORTANT point - number is multiplied by 3 MEANS number increases by 2 times..
so 2x=12...x=6

D
_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html


GMAT online Tutor

SVP
SVP
User avatar
D
Joined: 26 Mar 2013
Posts: 2010
Reviews Badge CAT Tests
Re: which of the five numbers is multiplied by 3?  [#permalink]

Show Tags

New post 24 Jan 2018, 03:31
selim wrote:
The average of the five members is 7. if one of the members is multiplied by 3, the average of the numbers increases to 9.4. which of the five numbers is multiplied by 3?

a)4
b)5
c)5.6
d)6
e) none of these



Let the numbers a,b,c,d,e

a+b+c+d+e= 5 *7..........1

If a is multiplied by 3 (or any number)

3a+b+c+d+e= 5 *9.4 (do not bother multiply now).............2

Subtract 1 from 2

2a = 5 (9.4 -7) = 5 * 2.4).........divide by 2

a = 5 * 1.2 = 6

Answer: D

Tip: Sometimes it is easier not rush multiply numbers
Board of Directors
User avatar
P
Status: QA & VA Forum Moderator
Joined: 11 Jun 2011
Posts: 4354
Location: India
GPA: 3.5
WE: Business Development (Commercial Banking)
GMAT ToolKit User Premium Member CAT Tests
which of the five numbers is multiplied by 3?  [#permalink]

Show Tags

New post 24 Jan 2018, 05:39
selim wrote:
The average of the five members is 7. if one of the members is multiplied by 3, the average of the numbers increases to 9.4. which of the five numbers is multiplied by 3?

a)4
b)5
c)5.6
d)6
e) none of these


\(a + b + c + d + e = 35\)--------------------->(I)
\(3a + b + c + d + e = 47\)------------------->(II)

\((II) - (I)\) : \(2a = 12\) , \(a = 6\), Answer must be (D)
_________________

Thanks and Regards

Abhishek....

PLEASE FOLLOW THE RULES FOR POSTING IN QA AND VA FORUM AND USE SEARCH FUNCTION BEFORE POSTING NEW QUESTIONS

How to use Search Function in GMAT Club | Rules for Posting in QA forum | Writing Mathematical Formulas |Rules for Posting in VA forum | Request Expert's Reply ( VA Forum Only )

GMAT Club Bot
which of the five numbers is multiplied by 3? &nbs [#permalink] 24 Jan 2018, 05:39
Display posts from previous: Sort by

which of the five numbers is multiplied by 3?

  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®.