It is currently 19 Oct 2017, 13:37

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

Events & Promotions in June
Open Detailed Calendar

The contents of a bag of marbles consist of 9 green marbles

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

Hide Tags

Director
Director
avatar
Status: Finally Done. Admitted in Kellogg for 2015 intake
Joined: 25 Jun 2011
Posts: 533

Kudos [?]: 4121 [0], given: 217

Location: United Kingdom
Concentration: International Business, Strategy
GMAT 1: 730 Q49 V45
GPA: 2.9
WE: Information Technology (Consulting)
The contents of a bag of marbles consist of 9 green marbles [#permalink]

Show Tags

New post 16 Mar 2012, 04:24
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  25% (medium)

Question Stats:

68% (01:08) correct 32% (01:17) wrong based on 247 sessions

HideShow timer Statistics

The contents of a bag of marbles consist of 9 green marbles and 16 blue marbles. How many blue marbles must be removed so that 60% of the marbles in the bag will be green?

(A) 1
(B) 6
(C) 7
(D) 9
(E) 10

Relatively easy question and I think I have a problem with the concept. Can someone please explain?
[Reveal] Spoiler: OA

_________________

Best Regards,
E.

MGMAT 1 --> 530
MGMAT 2--> 640
MGMAT 3 ---> 610
GMAT ==> 730


Last edited by Bunuel on 16 Mar 2012, 04:35, edited 1 time in total.
Edited the OA

Kudos [?]: 4121 [0], given: 217

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 41891

Kudos [?]: 128901 [0], given: 12183

Re: Number of green marbles [#permalink]

Show Tags

New post 16 Mar 2012, 04:34
enigma123 wrote:
The contents of a bag of marbles consist of 9 green marbles and 16 blue marbles. How many blue marbles must be removed so that 60% of the marbles in the bag will be green?

(A) 1
(B) 6
(C) 7
(D) 9
(E) 10

Relatively easy question and I think I have a problem with the concept. Can someone please explain?


Say we remove x blue marbles, so there will be 9+16-x marbles in the bag. We want 9 green marbles to compose 60% of this number: 0.6(9+16-x)=9 --> x=10.

Answer: E.
_________________

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

Kudos [?]: 128901 [0], given: 12183

Manager
Manager
avatar
Joined: 21 Sep 2011
Posts: 111

Kudos [?]: 16 [0], given: 18

Concentration: Entrepreneurship, General Management
GMAT 1: 530 Q42 V20
GMAT 2: 540 Q43 V28
GMAT 3: 680 Q48 V35
WE: Business Development (Hospitality and Tourism)
Re: The contents of a bag of marbles consist of 9 green marbles [#permalink]

Show Tags

New post 16 Mar 2012, 07:13
We have 9 green and 16 blue marbles.

60% = 9 green marbles
rest 40% = 6, which needs to blue marbles.

6 should be in the bag, so we need to remove 10 marbles.

IMO E.
_________________

KUDOS - if my post has helped you.

Kudos [?]: 16 [0], given: 18

Moderator
Moderator
User avatar
G
Joined: 01 Sep 2010
Posts: 3357

Kudos [?]: 9053 [0], given: 1154

Re: The contents of a bag of marbles consist of 9 green marbles [#permalink]

Show Tags

New post 02 Jun 2012, 04:00

Kudos [?]: 9053 [0], given: 1154

1 KUDOS received
Intern
Intern
avatar
Joined: 06 Aug 2012
Posts: 1

Kudos [?]: 1 [1], given: 6

Re: The contents of a bag of marbles consist of 9 green marbles [#permalink]

Show Tags

New post 21 Aug 2012, 11:14
1
This post received
KUDOS
I just set it up like this.

9/X marbles = .60 ==> solve for x equals 15 marbles. 25-10 = 15.

Kudos [?]: 1 [1], given: 6

GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 16651

Kudos [?]: 273 [0], given: 0

Premium Member
Re: The contents of a bag of marbles consist of 9 green marbles [#permalink]

Show Tags

New post 20 Sep 2013, 10:53
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

Kudos [?]: 273 [0], given: 0

Senior Manager
Senior Manager
User avatar
S
Joined: 25 Mar 2013
Posts: 275

Kudos [?]: 33 [0], given: 101

Location: United States
Concentration: Entrepreneurship, Marketing
GPA: 3.5
GMAT ToolKit User Reviews Badge
Re: The contents of a bag of marbles consist of 9 green marbles [#permalink]

Show Tags

New post 22 Sep 2013, 20:38
9 green, 16 blue = 25 marbles
60% = 9 marbles , 100% = 15 marbles
so in 15 9 green and 10 blue
_________________

I welcome analysis on my posts and kudo +1 if helpful. It helps me to improve my craft.Thank you

Kudos [?]: 33 [0], given: 101

Intern
Intern
avatar
Joined: 09 Mar 2010
Posts: 38

Kudos [?]: 23 [0], given: 17

Concentration: Technology, General Management
Schools: McCombs '14
GMAT ToolKit User
Re: The contents of a bag of marbles consist of 9 green marbles [#permalink]

Show Tags

New post 23 Sep 2013, 07:40
I Just did it this way,
Since the bag should contain 60% green marbles and rest Blue Marbles,

x/(9+16) = 60% ==> x= 15 ==> 9+ 6 , so 10 blue marbles will be removed.

Kudos [?]: 23 [0], given: 17

GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 16651

Kudos [?]: 273 [0], given: 0

Premium Member
Re: The contents of a bag of marbles consist of 9 green marbles [#permalink]

Show Tags

New post 21 Jan 2015, 07:35
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

Kudos [?]: 273 [0], given: 0

Expert Post
EMPOWERgmat Instructor
User avatar
P
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 9980

Kudos [?]: 3410 [0], given: 172

Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Re: The contents of a bag of marbles consist of 9 green marbles [#permalink]

Show Tags

New post 21 Jan 2015, 20:33
Hi All,

This question is rooted in basic arithmetic. Since the question asks how many marbles need to be removed and the answers ARE numbers, we can TEST THE ANSWERS until we find the one that "fits."

To start, we have a bag of marbles....
9 green
16 blue
25 total

We're asked to remove blue marbles until the green marbles make up 60% of the bag....

Right now, green marbles make up 9/25 = 36% of the bag, so we clearly need to remove a bunch of blue marbles to change this percentage. Looking at the answers, I'd TEST one of the larger options first...

Let's TEST D....

IF 9 blue marbles were removed, then we'd have...
9 green
7 blue
16 total
9/16 is NOT 60% exactly, but it's pretty close....

Let's TEST E...

IF 10 blue marbles were removed, then we'd have...
9 green
6 blue
15 total
9/15 IS 60%, so this MUST be the answer!

Final Answer:
[Reveal] Spoiler:
E


GMAT assassins aren't born, they're made,
Rich
_________________

760+: Learn What GMAT Assassins Do to Score at the Highest Levels
Contact Rich at: Rich.C@empowergmat.com

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests Free
  Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/

***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************

Kudos [?]: 3410 [0], given: 172

Expert Post
EMPOWERgmat Instructor
User avatar
P
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 9980

Kudos [?]: 3410 [0], given: 172

Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Re: The contents of a bag of marbles consist of 9 green marbles [#permalink]

Show Tags

New post 21 Jan 2015, 20:33
Hi All,

This question is rooted in basic arithmetic. Since the question asks how many marbles need to be removed and the answers ARE numbers, we can TEST THE ANSWERS until we find the one that "fits."

To start, we have a bag of marbles....
9 green
16 blue
25 total

We're asked to remove blue marbles until the green marbles make up 60% of the bag....

Right now, green marbles make up 9/25 = 36% of the bag, so we clearly need to remove a bunch of blue marbles to change this percentage. Looking at the answers, I'd TEST one of the larger options first...

Let's TEST D....

IF 9 blue marbles were removed, then we'd have...
9 green
7 blue
16 total
9/16 is NOT 60% exactly, but it's pretty close....

Let's TEST E...

IF 10 blue marbles were removed, then we'd have...
9 green
6 blue
15 total
9/15 IS 60%, so this MUST be the answer!

Final Answer:
[Reveal] Spoiler:
E


GMAT assassins aren't born, they're made,
Rich
_________________

760+: Learn What GMAT Assassins Do to Score at the Highest Levels
Contact Rich at: Rich.C@empowergmat.com

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests Free
  Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/

***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************

Kudos [?]: 3410 [0], given: 172

Re: The contents of a bag of marbles consist of 9 green marbles   [#permalink] 21 Jan 2015, 20:33
Display posts from previous: Sort by

The contents of a bag of marbles consist of 9 green marbles

  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 | 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®.