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

It is currently 16 Oct 2019, 13:01

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

Each of the four identical containers (A,B,C and D) contains ‘b’ balls

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

Hide Tags

Find Similar Topics 
Current Student
avatar
B
Joined: 22 Jul 2014
Posts: 120
Concentration: General Management, Finance
GMAT 1: 670 Q48 V34
WE: Engineering (Energy and Utilities)
GMAT ToolKit User Reviews Badge
Each of the four identical containers (A,B,C and D) contains ‘b’ balls  [#permalink]

Show Tags

New post 27 Aug 2014, 23:42
13
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

63% (02:19) correct 37% (02:25) wrong based on 155 sessions

HideShow timer Statistics

Each of the four identical containers (A,B,C and D) contains ‘b’ balls. When some of the balls from container A are moved to the other 3 containers, the ratio of the number of the balls in A,B,C and D are in the ratio 1:4:4:3. How many balls are moved from the first container in terms of ‘b’?

A) (5/6)b
B) (1/6)b
C) (2/6)b
D) (4/6)b
E) (3/6)b




Source: 4Gmat
Most Helpful Community Reply
SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1749
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: Each of the four identical containers (A,B,C and D) contains ‘b’  [#permalink]

Show Tags

New post 28 Aug 2014, 00:16
6
alphonsa wrote:
Each of the four identical containers (A,B,C and D) contains ‘b’ balls. When some of the balls from container A are moved to the other 3 containers, the ratio of the number of the balls in A,B,C and D are in the ratio 1:4:4:3. How many balls are moved from the first container in terms of ‘b’?

A) (5/6)b
B) (1/6)b
C) (2/6)b
D) (4/6)b
E) (3/6)b

Source: 4Gmat


After ball movement, the ratio = 1:4:4:3

Before ball movement, all 4 containers had same "b" no. of balls = 3:3:3:3

Comparing before/after ratios.....

It means 2 balls (out of 3) were taken out from A; 1 went in B & 1 went in C (No change in D)

Equation \(= \frac{2b}{3} = \frac{4b}{6}\)

Answer = D
_________________
Kindly press "+1 Kudos" to appreciate :)
General Discussion
Current Student
avatar
B
Joined: 22 Jul 2014
Posts: 120
Concentration: General Management, Finance
GMAT 1: 670 Q48 V34
WE: Engineering (Energy and Utilities)
GMAT ToolKit User Reviews Badge
Re: Each of the four identical containers (A,B,C and D) contains ‘b’ balls  [#permalink]

Show Tags

New post 27 Aug 2014, 23:44
I got the answer be taking a number for 'b' .

But can someone tell me there is a better method to solve this. If deriving is better than taking values.



Also I am able to get answers for Quant but invariably it takes a lot of time sometimes to get the answer.

Would you suggest some method to improve speed :(

I don't want to miss out on questions because of speed.

Any suggestions to build speed? :(
Current Student
User avatar
P
Status: Chasing my MBB Dream!
Joined: 29 Aug 2012
Posts: 1100
Location: United States (DC)
WE: General Management (Aerospace and Defense)
GMAT ToolKit User Reviews Badge
Each of the four identical containers (A,B,C and D) contains ‘b’ balls  [#permalink]

Show Tags

New post 28 Aug 2014, 00:00
1
alphonsa wrote:
I got the answer be taking a number for 'b' .

But can someone tell me there is a better method to solve this. If deriving is better than taking values.



Also I am able to get answers for Quant but invariably it takes a lot of time sometimes to get the answer.

Would you suggest some method to improve speed :(

I don't want to miss out on questions because of speed.

Any suggestions to build speed? :(



We have different methods to approach this problem,

1st look at the answer choices, all the values contain denominator 6. So B must be a multiple of 6, only then the value for all the answer choices will be an integer.

Since we cannot have the number of balls in fractions.

Now plugging a value. Clue here is answer choices. So take b=6.

If all the jars has same number of (b) balls initially, then the total number of balls will be 6+6+6+6= 4*6= 24.

We are removing some balls from jar A and moving it to other jars. The ratio is 1:4:4:3.

Notice that, we are not adding new balls from outside. So the sum will be always equal to 24.

Let x be the multiplier, then

1x+4x+4x+3x= 24.

12x=24

x=2.

Now, the number of balls in each jar will be,

A:2
B:4*2=8
C:4*2=8
D: 3*2=6

Initially we had 6 balls in jar A. Now we have 2 balls. So 4 balls removed from the jar A.

Check the answer choices which gives us the value of 4, when we substitute b=6.

Only one option does that.

So Answer is D.

Hope it helps.
_________________
Intern
Intern
avatar
Joined: 27 Aug 2014
Posts: 27
GMAT Date: 09-27-2014
GMAT ToolKit User
Re: Each of the four identical containers (A,B,C and D) contains ‘b’ balls  [#permalink]

Show Tags

New post 28 Aug 2014, 00:39
Paresh's approach is the quickest that I know of. Although the numbers are relatively easy in this question, I'd choose the denominator of the solutions as b (ie 6 in this question), that way I can be sure of getting an integer.
Current Student
User avatar
D
Joined: 12 Aug 2015
Posts: 2568
Schools: Boston U '20 (M)
GRE 1: Q169 V154
GMAT ToolKit User
Re: Each of the four identical containers (A,B,C and D) contains ‘b’ balls  [#permalink]

Show Tags

New post 06 Mar 2016, 20:55
1
Gnpth wrote:
alphonsa wrote:
I got the answer be taking a number for 'b' .

But can someone tell me there is a better method to solve this. If deriving is better than taking values.



Also I am able to get answers for Quant but invariably it takes a lot of time sometimes to get the answer.

Would you suggest some method to improve speed :(

I don't want to miss out on questions because of speed.

Any suggestions to build speed? :(



We have different methods to approach this problem,

1st look at the answer choices, all the values contain denominator 6. So B must be a multiple of 6, only then the value for all the answer choices will be an integer.

Since we cannot have the number of balls in fractions.

Now plugging a value. Clue here is answer choices. So take b=6.

If all the jars has same number of (b) balls initially, then the total number of balls will be 6+6+6+6= 4*6= 24.

We are removing some balls from jar A and moving it to other jars. The ratio is 1:4:4:3.

Notice that, we are not adding new balls from outside. So the sum will be always equal to 24.

Let x be the multiplier, then

1x+4x+4x+3x= 24.

12x=24

x=2.

Now, the number of balls in each jar will be,

A:2
B:4*2=8
C:4*2=8
D: 3*2=6

Initially we had 6 balls in jar A. Now we have 2 balls. So 4 balls removed from the jar A.

Check the answer choices which gives us the value of 4, when we substitute b=6.

Only one option does that.

So Answer is D.

Hope it helps.



here is my approach
each jar has initially b balls
next after removing => x,4x,4x,3x
balls in A = x+4x-b+4x-b+3x-b = 12x-3b
b=12x-3b => x=b/3

now balls removed from A= b-b/3 = 2b/3 =4b/6 => option D..

is it wrong to think like this?
Anyways your solution is awesome and it takes less time..

thanks
_________________
Board of Directors
User avatar
P
Joined: 17 Jul 2014
Posts: 2513
Location: United States (IL)
Concentration: Finance, Economics
GMAT 1: 650 Q49 V30
GPA: 3.92
WE: General Management (Transportation)
GMAT ToolKit User Reviews Badge
Re: Each of the four identical containers (A,B,C and D) contains ‘b’ balls  [#permalink]

Show Tags

New post 06 Apr 2016, 18:35
1
alphonsa wrote:
Each of the four identical containers (A,B,C and D) contains ‘b’ balls. When some of the balls from container A are moved to the other 3 containers, the ratio of the number of the balls in A,B,C and D are in the ratio 1:4:4:3. How many balls are moved from the first container in terms of ‘b’?

A) (5/6)b
B) (1/6)b
C) (2/6)b
D) (4/6)b
E) (3/6)b




Source: 4Gmat


i solved it algebraically and it took me under 1 minute to do so.

we have 1x:4x:4x:3x = total =12x.
we know that 12x=4b
b=3x

now, we are left with 1 x, then 2x must have been removed.
(2x/3x)*b
since we need 4 in denominator, multiply everything by 2:
(4/6)b
Retired Moderator
avatar
D
Joined: 25 Feb 2013
Posts: 1178
Location: India
GPA: 3.82
GMAT ToolKit User Reviews Badge
Re: Each of the four identical containers (A,B,C and D) contains ‘b’ balls  [#permalink]

Show Tags

New post 27 Oct 2017, 21:28
alphonsa wrote:
Each of the four identical containers (A,B,C and D) contains ‘b’ balls. When some of the balls from container A are moved to the other 3 containers, the ratio of the number of the balls in A,B,C and D are in the ratio 1:4:4:3. How many balls are moved from the first container in terms of ‘b’?

A) (5/6)b
B) (1/6)b
C) (2/6)b
D) (4/6)b
E) (3/6)b

Source: 4Gmat


Let \(y\) balls be transferred from A to other three containers. we need to find the value of \(y\)

After the transfer number of ball in each container be \(x\), \(4x\), \(4x\) & \(3x\)

number of balls left in container A; \(x= b-y\)

And total number of balls in the remaining three containers after increment of \(y\); \((4x+4x+3x)=3b+y => 11x=3b+y\)

substitute the value of \(x\) in the above equation to get

\(11(b-y)=3b+y\), solve this to get

\(y= \frac{8b}{12} => \frac{4b}{6}\)

Option D
Intern
Intern
avatar
Joined: 09 May 2016
Posts: 2
Each of the four identical containers (A,B,C and D) contains ‘b’ balls  [#permalink]

Show Tags

New post 20 Aug 2019, 12:49
1
Another way to solve:

Total number of balls if all containers have 'b' balls = 4b

assume x balls were taken out of the first container and y, m, n balls were put in the rest three containers.

b-x: b+y: b+m: b+n = 1:4:4:3 ..... [1+4+4+3=12]

It can be said that:
(b-x) = (1/12)*(4b) [balls in first container are 1/12th of total balls]
(b+y) = (4/12)*(4b) [balls in second container are 4/12th of total balls]
(b+m) = (4/12)*(4b) [balls in third container are 4/12th of total balls]
(b+n) = (3/12)*(4b) [balls in fourth container are 3/12th of total balls]

pick any one of the above to solve:

b-x=(1/12)*(4b)
b-x=b/3
x=2b/3

2b/3 is the total number of balls removed from container 1.

which can also be written as 4b/6.
Manager
Manager
avatar
B
Joined: 20 Jul 2012
Posts: 117
GMAT 1: 650 Q47 V33
Re: Each of the four identical containers (A,B,C and D) contains ‘b’ balls  [#permalink]

Show Tags

New post 20 Aug 2019, 13:41
alphonsa wrote:
Each of the four identical containers (A,B,C and D) contains ‘b’ balls. When some of the balls from container A are moved to the other 3 containers, the ratio of the number of the balls in A,B,C and D are in the ratio 1:4:4:3. How many balls are moved from the first container in terms of ‘b’?

A) (5/6)b
B) (1/6)b
C) (2/6)b
D) (4/6)b
E) (3/6)b




Source: 4Gmat


A contains b-2x-y
B contains b+x
C contains b+x
D contains b+y

Now the ratio is 1:4:4:3

So, b+x = 4(b-2x-y)
=> 9x+4y = 3b .......................1

and b+y = 3(b-2x-y)
=> 6x + 4y = 2b ......................2

Solving (Subtracting 2 from 1)
3x = b
so y = 0

So, balls taken out from A = 2x-y = 2b/3 = 4b/6
GMAT Club Bot
Re: Each of the four identical containers (A,B,C and D) contains ‘b’ balls   [#permalink] 20 Aug 2019, 13:41
Display posts from previous: Sort by

Each of the four identical containers (A,B,C and D) contains ‘b’ balls

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





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