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

 It is currently 27 May 2015, 18:52

### 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

# Bag A contains red, white and blue marbles such that the red

 Question banks Downloads My Bookmarks Reviews Important topics
Author Message
TAGS:
Intern
Joined: 06 Apr 2007
Posts: 9
Followers: 0

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

Bag A contains red, white and blue marbles such that the red [#permalink]  28 May 2007, 19:12
Bag A contains red, white and blue marbles such that the red to white marble ratio is 1:3 and the white to blue marble ratio is 2:3. Bag B contains red and white marbles in the ratio of 1:4. Together, the two bags contain 30 white marbles. How many red marbles could be in bag A?
1
3
4
6
8

I really dislike their explanation so could someone come up with a clean one?thanks
Director
Joined: 26 Feb 2006
Posts: 905
Followers: 4

Kudos [?]: 54 [0], given: 0

Re: Marbles - ManhattanGMat [#permalink]  28 May 2007, 19:44
nxrfelix wrote:
Bag A contains red, white and blue marbles such that the red to white marble ratio is 1:3 and the white to blue marble ratio is 2:3. Bag B contains red and white marbles in the ratio of 1:4. Together, the two bags contain 30 white marbles. How many red marbles could be in bag A?
1
3
4
6
8

I really dislike their explanation so could someone come up with a clean one?thanks

W(a) = 4r(a)
W(b) = 3r(b)

W(a) + W(b) = 30
4r(a) + 3r(b) = 30

if r(a) = 3 and r(b) = 6, then the sum becoms 30. therefore, r(a) = 3.
Intern
Joined: 16 May 2007
Posts: 18
Followers: 0

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

[#permalink]  29 May 2007, 11:06
I got 6

I am assuming I have only whole marbles in each bag.

The problem says that for bag A:
r:w = 1:3 and w:b = 2:3
this means that r:w:b = 1: 3: 4.5
So out of all answer choices the only ones that give you combinations of whole marbles are:
4 -> 4red, 12white, 18blue
6 -> 6red, 18white, 27blue
8 -> 8red, 24white, 36blue

For bag B, a ratio of r:w = 1:4 means that we have the following combinations possible:
1red, 4white
2red, 8white
3red, 12white
4red, 16white
5red, 20white
6red, 24white
7red, 28white and so on...

The only possible combination b/w bag A and bag B such that the white marbles in bag A plus the white marbles in bag B equal 30 is:
Bag A:
6 red, 18white, 27blue, and
Bag B:
3 red, 12 white

18+12 = 30, so

Manager
Joined: 22 May 2007
Posts: 121
Followers: 1

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

[#permalink]  29 May 2007, 11:21
6 it is! Same logic. Bag A ratio - 2-6-9 , bag B 1-4
Intern
Joined: 06 Apr 2007
Posts: 9
Followers: 0

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

[#permalink]  29 May 2007, 18:55
joroivanov wrote:
I got 6

I am assuming I have only whole marbles in each bag.

The problem says that for bag A:
r:w = 1:3 and w:b = 2:3
this means that r:w:b = 1: 3: 4.5
So out of all answer choices the only ones that give you combinations of whole marbles are:
4 -> 4red, 12white, 18blue
6 -> 6red, 18white, 27blue
8 -> 8red, 24white, 36blue

For bag B, a ratio of r:w = 1:4 means that we have the following combinations possible:
1red, 4white
2red, 8white
3red, 12white
4red, 16white
5red, 20white
6red, 24white
7red, 28white and so on...

The only possible combination b/w bag A and bag B such that the white marbles in bag A plus the white marbles in bag B equal 30 is:
Bag A:
6 red, 18white, 27blue, and
Bag B:
3 red, 12 white

18+12 = 30, so

this is a great solution!much better than what mgmat gave...
Director
Joined: 03 Sep 2006
Posts: 884
Followers: 6

Kudos [?]: 271 [0], given: 33

[#permalink]  29 May 2007, 20:28
nxrfelix wrote:
joroivanov wrote:
I got 6

I am assuming I have only whole marbles in each bag.

The problem says that for bag A:
r:w = 1:3 and w:b = 2:3
this means that r:w:b = 1: 3: 4.5
So out of all answer choices the only ones that give you combinations of whole marbles are:
4 -> 4red, 12white, 18blue
6 -> 6red, 18white, 27blue
8 -> 8red, 24white, 36blue

For bag B, a ratio of r:w = 1:4 means that we have the following combinations possible:
1red, 4white
2red, 8white
3red, 12white
4red, 16white
5red, 20white
6red, 24white
7red, 28white and so on...

The only possible combination b/w bag A and bag B such that the white marbles in bag A plus the white marbles in bag B equal 30 is:
Bag A:
6 red, 18white, 27blue, and
Bag B:
3 red, 12 white

18+12 = 30, so

this is a great solution!much better than what mgmat gave...

BAG A

2:6:9

Bag B

1:4

after that it's easy
[#permalink] 29 May 2007, 20:28
Similar topics Replies Last post
Similar
Topics:
18 Bag A contains red, white and blue marbles such that the red 11 08 Sep 2010, 19:56
12 Bag A contains red, white and blue marbles such that the red 30 29 Jun 2007, 14:38
4 Bag A contains red, white and blue marbles such that the red to white 8 01 Jul 2008, 10:25
51 A bag of 10 marbles contains 3 red marbles and 7 blue 33 06 Dec 2007, 14:24
A bag contains 10 marbles - 3 red, 2 green and 5 blue 7 27 Jul 2006, 00:25
Display posts from previous: Sort by

# Bag A contains red, white and blue marbles such that the red

 Question banks Downloads My Bookmarks Reviews Important topics

 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®.