|
Author |
Message |
|
TAGS:
|
|
|
Senior Manager
Joined: 08 Jan 2009
Posts: 338
Followers: 2
Kudos [?]:
42
[0], given: 5
|
I have a question:
Why did we take the Number of marbles in BAG A and BAG B to be equal as K? It did not state in the question?
I both were different quantities they would be slit up as : 2x : 6x: 9 x
and BAG B as : 1y : 4y
then i took 6x + 4 y = 30 3x + 2y = 15
i took y = 1 x = 13/3 not possible
y = 2 x = 11/3 not possible
y = 3 x = 3 possible.
So i since x = 3 i got R = 6. Is my approach correct.
|
|
|
|
|
|
|
Intern
Joined: 29 Dec 2006
Posts: 33
Followers: 0
Kudos [?]:
0
[0], given: 0
|
tkarthi4u wrote: I have a question:
Why did we take the Number of marbles in BAG A and BAG B to be equal as K? It did not state in the question?
I both were different quantities they would be slit up as : 2x : 6x: 9 x
and BAG B as : 1y : 4y
then i took 6x + 4 y = 30 3x + 2y = 15
i took y = 1 x = 13/3 not possible
y = 2 x = 11/3 not possible
y = 3 x = 3 possible.
So i since x = 3 i got R = 6. Is my approach correct. because 30 is the quantity from both bags, you can use the same variable; i.e. 6x+4x=30, x=3. then use this ratio for both bags.
|
|
|
|
|
|
Manager
Joined: 02 Mar 2009
Posts: 138
Followers: 1
Kudos [?]:
24
[0], given: 0
|
I highly doubt that. I proceeded the same way as tkarthi. I dont think you can add two distinct ratios together.
|
|
|
|
|
|
Manager
Joined: 01 Aug 2008
Posts: 120
Followers: 1
Kudos [?]:
8
[0], given: 2
|
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 D
_________________
==============================================
Do not answer without sharing the reasoning behind ur choice
-----------------------------------------------------------
Working on my weakness : GMAT Verbal
------------------------------------------------------------
Ask:
Why, What, How, When, Where, Who
==============================================
|
|
|
|
|
|
Manager
Joined: 08 Feb 2009
Posts: 149
Schools: Anderson
Followers: 3
Kudos [?]:
26
[0], given: 3
|
Re: Ratio of Marbles [#permalink]
 02 Jun 2009, 08:45
Combined Ratio of marbles in
Bag A \Rightarrow 2:6:9 \Rightarrow a multiple of 6. Let the while marbles = 6x
Let White marbles in Bag B = W_b
Let White marbles in Bag A = W_a
Let Red marbles in Bag A = R_a
Bag B has (30-6x), which is a multiple of 4.
If x = 1, W_b = 24, W_a = 6, \Rightarrow R_a = 2 , which is not in the solution.
If x = 2, (30-12) is not a multiple of 4
If x = 3, W_b = 12, W_a = 18, \Rightarrow R_a = 6 , which is IN the solution.
If x = 4, (30-24) is not a multiple of 4.
Thus, answer is D.
|
|
|
|
|
|
Manager
Joined: 01 Aug 2008
Posts: 120
Followers: 1
Kudos [?]:
8
[0], given: 2
|
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 MGMAT/CAT1/Ratios/PS
_________________
==============================================
Do not answer without sharing the reasoning behind ur choice
-----------------------------------------------------------
Working on my weakness : GMAT Verbal
------------------------------------------------------------
Ask:
Why, What, How, When, Where, Who
==============================================
|
|
|
|
|
|
Manager
Joined: 30 May 2009
Posts: 223
Followers: 3
Kudos [?]:
33
[0], given: 0
|
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
Solution - Combined ratio of Red:White:Blue marbles in bag A is 2:6:9.
And ratio of Red:White in Bag B = 1:4
So total white marbled in 2 bags combined = 30 (given)
=> 6x + 4x = 30
=> x = 3
Hence red marbles in Bag A = 2x = 2*3 = 6
I would go with D. Whats the OA?
|
|
|
|
|
|
Senior Manager
Joined: 23 Jun 2009
Posts: 368
Location: Turkey
Schools: UPenn, UMich, HKS, UCB, Chicago
Followers: 4
Kudos [?]:
86
[0], given: 60
|
Answer is D.
SdRandom, there is an error in your solution.
Your ratios are right.
2/6/9 in A
1/4 in B
That makes
6x + 4y=30 This is where you have done wrong.
After it. We must look at the choices.
Red no's must be even (2/6/9 ratio)
So it may be 4, 6 or 8.
If red is 4 => whites in A becomes 12; whites in B becomes 18 (30-12) => 1/4 ratio becomes impossible thus 4 is wrong.
If red is 8 => whites in A becomes 24; whites in B becomes 6 => 1/4 ratio becomes impossible
When red is 6 => whites in A becomes 18; in B becomes 12 thus 1/4 ratio becomes possible
|
|
|
|
|
|
Director
Joined: 25 Oct 2008
Posts: 618
Location: Kolkata,India
Followers: 6
Kudos [?]:
94
[0], given: 100
|
Is my process correct? A R:W:B =2:6:9 B R:W=1:4 Now.A+B has 30 white marbles. Out of this 30 B has 4/5 x 30 = 24 marbles,therefore the rest 30-24=6 must be from A.  Hence,D.
_________________
countdown-beginshas-ended-85483-40.html#p649902
|
|
|
|
|
|
Intern
Joined: 07 Jul 2010
Posts: 7
Followers: 0
Kudos [?]:
0
[0], given: 0
|
ALSO 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? A) 1 B) 3 C) 4 D) 6 E) 8 Please explain. I did not understand the explanation given. Thanks
|
|
|
|
|
|
GMAT Forum Moderator
Status: Accepting donations for the mohater MBA fund
Joined: 05 Feb 2008
Posts: 1821
Location: United States
Concentration: Healthcare, Economics
GMAT 1: 710 Q48 V38
GMAT 2: Q V
GPA: 3.54
WE: Accounting (Manufacturing)
Followers: 39
Kudos [?]:
324
[0], given: 233
|
Re: help please :) [#permalink]
29 Aug 2010, 15:47
Already posted: marbel-ratios-80692.htmlPlease search in the future. Locked.
_________________
Strategy Discussion Thread | Strategy Master | GMAT Debrief| Please discuss strategies in discussion thread. Master thread will be updated accordingly. | GC Member Write Ups
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
Intern
Joined: 07 Jul 2010
Posts: 7
Followers: 0
Kudos [?]:
0
[0], given: 0
|
Re: help please :) [#permalink]
29 Aug 2010, 15:49
sorry! This probably sounds stupid but I didnt know that we can search questions. Thanks!
|
|
|
|
|
|
Manager
Joined: 16 Feb 2010
Posts: 232
Followers: 2
Kudos [?]:
27
[0], given: 16
|
Re: help please :) [#permalink]
29 Aug 2010, 17:54
spatel121990 wrote: ALSO 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? A) 1 B) 3 C) 4 D) 6 E) 8 Please explain. I did not understand the explanation given. Thanks BAG A: R to W to B is 2 to 6 to 9 BAG B: R W is 1 to 4 white in both is 30 therefore using 4+6 = 10 30/10 = 3 therefore 3 *6 = 18 white in bag a ration is 2 to 6 therefore if 18w, 18*2/6 = 6red D
|
|
|
|
|
|
Senior Manager
Status: Do and Die!!
Joined: 15 Sep 2010
Posts: 335
Followers: 1
Kudos [?]:
27
[0], given: 192
|
MGMT ratio problem [#permalink]
02 Aug 2011, 22:38
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 Bag A: R/w = 1/3 and w/b=2/3 Bag B: R/w = 1/4 Number of White marbles in A and B is 30 . i.e A+B =30 so in Bag B Number of white marbles will be 30/5 * 4 = 24 since A+B = 30 => B= 24 then in Bag A number of white marbles will be 6 Now R/w = 1/3 => R/6 = 1/3 => R=2But there is NO 2. what i'm doing wrong. please explain. regards
_________________
I'm the Dumbest of All !!
|
|
|
|
|
|
Math Forum Moderator
Joined: 20 Dec 2010
Posts: 2098
Followers: 109
Kudos [?]:
667
[1] , given: 376
|
Re: MGMT ratio problem [#permalink]
02 Aug 2011, 22:59
1
This post received
KUDOS
shrive555 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
Bag A: R:W:B|R:W:B 1x:3x:-|2x:6x:- -:2x:3x|-:6x:9x Bag A: R:W:B 2x:6x:9x Bag B: R:W 1y:4y If we just consider white marbles now: 6x+4y=30 y=(30-6x)/4 So, x=1; y=6 x=2; y=Non integer. Ignore x=3; y=3 x=4; y=Non integer x=5; y=0(Not possible) Thus, x can be either 1 or 3. If x=1; Bag A: R:W:B 2x:6x:9x R=2*1=2 If x=3; R=2*3=6 So, both 2 and 6 are possible numbers of red marbles in Bag A. Ans: "D"
_________________
~fluke
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
Senior Manager
Status: Do and Die!!
Joined: 15 Sep 2010
Posts: 335
Followers: 1
Kudos [?]:
27
[0], given: 192
|
Re: MGMT ratio problem [#permalink]
02 Aug 2011, 23:14
fluke wrote: shrive555 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
Bag A: R:W:B|R:W:B 1x:3x:-|2x:6x:- -:2x:3x|-:6x:9x Bag A:
R:W:B
2x:6x:9xBag B: R:W 1y:4y If we just consider white marbles now: 6x+4y=30 y=(30-6x)/4 So, x=1; y=6 x=2; y=Non integer. Ignore x=3; y=3 x=4; y=Non integer x=5; y=0(Not possible) Thus, x can be either 1 or 3. If x=1; Bag A: R:W:B 2x:6x:9x R=2*1=2 If x=3; R=2*3=6 So, both 2 and 6 are possible numbers of red marbles in Bag A. Ans: "D" Thank you for your detail explanation. just little confusion. how did you get the red part. because i have to solve it through making equations R/w = 1/3 w/b=2/3 => R/b = 2/9 after this i don't know how to set up R:W:B I assume that you have used some short cut. 
_________________
I'm the Dumbest of All !!
|
|
|
|
|
|
Math Forum Moderator
Joined: 20 Dec 2010
Posts: 2098
Followers: 109
Kudos [?]:
667
[1] , given: 376
|
Re: MGMT ratio problem [#permalink]
02 Aug 2011, 23:22
1
This post received
KUDOS
shrive555 wrote: Thank you for your detail explanation. just little confusion. how did you get the red part. because i have to solve it through making equations R/w = 1/3 w/b=2/3 => R/b = 2/9 after this i don't know how to set up R:W:B I assume that you have used some short cut. Not really; Just take the LCM of the common term: R:W=1:3 --------1 W:B=2:3 --------2 Here W is common; Take the LCM of 2,3=6 So, eq 1 needs to be multiplied by 2: R:W=(1:3)*2=2:6---------3 So, eq 2 needs to be multiplied by 3: W:B=(2:3)*3=6:9---------4 Now; 3 and 4 are both 6 whites; we can join them R:W:B 2:6:9
_________________
~fluke
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
Manager
Joined: 27 Dec 2007
Posts: 76
Followers: 0
Kudos [?]:
7
[0], given: 1
|
Re: MGMT ratio problem [#permalink]
03 Aug 2011, 09:00
you guys are very much right 2 / 6 are the options possible
|
|
|
|
|
|
Intern
Joined: 27 Feb 2011
Posts: 49
Followers: 0
Kudos [?]:
0
[0], given: 9
|
Re: MGMT ratio problem [#permalink]
03 Aug 2011, 13:03
good question .. Bag A R:W:B = 2x: 6x: 9x and Bag B R:W = y:4y
6x + 4y = 30 => 3x + 2y = 15 ..
the only +ve integers that satisfy the above is 1, 6 and 3, 3 ..
red marbles in Bag A = 2x = 2 or 6 => answer is D
|
|
|
|
|
|
Intern
Joined: 04 Sep 2009
Posts: 49
Followers: 1
Kudos [?]:
3
[0], given: 9
|
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 [highlight]red marbles could be in bag A[/highlight]? [/[color=#40FF00]color] a 1 b 3 c 4 d 6 e 8
_________________
Aeros
"Why are you trying so hard to fit in when you were born to stand out?"
"Do or do not. There is no 'try'..."
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Similar topics |
Author |
Replies |
Last post |
|
Similar
Topics:
|
 |
|
|
A bag contains six marbles: two red, two blue, and two
|
vivek_dj |
3 |
05 Jan 2004, 13:39 |
|
|
|
|
A bag contains 3 red, 2 white, and 6 blue marbles. What is
|
afife76 |
7 |
09 Aug 2004, 13:33 |
|
|
|
|
Bag A contains red, white and blue marbles such that the red
|
nxrfelix |
5 |
28 May 2007, 20:12 |
 |
16
|
 |
A bag of 10 marbles contains 3 red marbles and 7 blue
|
bmwhype2 |
21 |
06 Dec 2007, 15:24 |
|
|
3
|
|
Bag A contains red, white and blue marbles such that the red
|
vigneshpandi |
4 |
08 Sep 2010, 20:56 |
|
|
|
|
|
|
close
