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

 It is currently 24 Aug 2016, 18:17

### 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

# 3 boys and 3 girls

Author Message
TAGS:

### Hide Tags

Senior Manager
Status: Do and Die!!
Joined: 15 Sep 2010
Posts: 326
Followers: 1

Kudos [?]: 355 [0], given: 193

3 boys and 3 girls [#permalink]

### Show Tags

19 Aug 2011, 23:59
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 1 sessions

### HideShow timer Statistics

in how many different ways can 3 boys and 3 girls be seated in a row of 6 chairs such that the girls are not separated and boys are not separated ?

i have no idea how to solve this question. Please Explain

_________________

I'm the Dumbest of All !!

Senior Manager
Status: Do and Die!!
Joined: 15 Sep 2010
Posts: 326
Followers: 1

Kudos [?]: 355 [0], given: 193

Re: 3 boys and 3 girls [#permalink]

### Show Tags

20 Aug 2011, 00:15
DeeptiM wrote:

i'm assuming that you tried 6C3 = 6!/3!*3! = 20. i don't know if its right or wrong because if this problem is thought in terms of slotting method i don't think, there could be 20 ways. because BBB GGG ... you can't separate them . and you have six chairs. Now i don't know if the chairs are placed next to each other or in circular shape. . .
_________________

I'm the Dumbest of All !!

Director
Joined: 01 Feb 2011
Posts: 757
Followers: 14

Kudos [?]: 100 [0], given: 42

Re: 3 boys and 3 girls [#permalink]

### Show Tags

20 Aug 2011, 15:34
girls and boys can be separated only through the following arrangements.

B B B G G G

G G G B B B

total arrangements = 6!/(3! 2!) = 20

total arrangements in which girls and boys are not separated = total arrangements - total arrangements in which they
are separated.

= 20 - 2 =18

Intern
Joined: 19 Aug 2011
Posts: 4
Followers: 0

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

Re: 3 boys and 3 girls [#permalink]

### Show Tags

20 Aug 2011, 16:25
Since Boys and Girls have to be together, we have two consider them as two groups:

Boys can be arranged in 3! ways.
Girls can be arranged in 3! ways.
Group can be arranged in 2! ways.

So the total no of ways should be 3!*3!*2!=72.
Senior Manager
Status: Do and Die!!
Joined: 15 Sep 2010
Posts: 326
Followers: 1

Kudos [?]: 355 [0], given: 193

Re: 3 boys and 3 girls [#permalink]

### Show Tags

22 Aug 2011, 21:34
Spidy001 wrote:
girls and boys can be separated only through the following arrangements.

B B B G G G

G G G B B B

total arrangements = 6!/(3! 2!) = 20

total arrangements in which girls and boys are not separated = total arrangements - total arrangements in which they
are separated.

= 20 - 2 =18

isn't it 20 the correct answer. why 2 has been subtracted from 20?

i don't have OA
_________________

I'm the Dumbest of All !!

Senior Manager
Status: Do and Die!!
Joined: 15 Sep 2010
Posts: 326
Followers: 1

Kudos [?]: 355 [0], given: 193

Re: 3 boys and 3 girls [#permalink]

### Show Tags

22 Aug 2011, 21:37
nish21in wrote:
Since Boys and Girls have to be together, we have two consider them as two groups:

Boys can be arranged in 3! ways.
Girls can be arranged in 3! ways.
Group can be arranged in 2! ways.

So the total no of ways should be 3!*3!*2!=72.

it can be 72 . i guess
_________________

I'm the Dumbest of All !!

Last edited by shrive555 on 13 Oct 2011, 09:54, edited 1 time in total.
Senior Manager
Joined: 11 May 2011
Posts: 373
Location: US
Followers: 3

Kudos [?]: 89 [0], given: 46

Re: 3 boys and 3 girls [#permalink]

### Show Tags

22 Aug 2011, 21:54
shrive555 wrote:
nish21in wrote:
Since Boys and Girls have to be together, we have two consider them as two groups:

Boys can be arranged in 3! ways.
Girls can be arranged in 3! ways.
Group can be arranged in 2! ways.

So the total no of ways should be 3!*3!*2!=72.

it can't be 72 . i guess

shrive555 is right..!!

Cheers.!
_________________

-----------------------------------------------------------------------------------------
What you do TODAY is important because you're exchanging a day of your life for it!
-----------------------------------------------------------------------------------------

Manager
Status: Still Struggling
Joined: 03 Nov 2010
Posts: 138
Location: India
GMAT Date: 10-15-2011
GPA: 3.71
WE: Information Technology (Computer Software)
Followers: 5

Kudos [?]: 66 [0], given: 8

Re: 3 boys and 3 girls [#permalink]

### Show Tags

22 Aug 2011, 21:56
I second 72..
total ways to arrange boys : 3!
total ways of arrange girls : 3!
if they are not to be seperated : 2!
total combinations : 3! * 3! *2! = 72

anyone who has not got the same ans, can u please explain what wrong here?
_________________

Knewton Free Test 10/03 - 710 (49/37)
Princeton Free Test 10/08 - 610 (44/31)
Kaplan Test 1- 10/10 - 630
Veritas Prep- 10/11 - 630 (42/37)
MGMAT 1 - 10/12 - 680 (45/34)

Intern
Joined: 11 May 2011
Posts: 22
Followers: 0

Kudos [?]: 20 [1] , given: 1

Re: 3 boys and 3 girls [#permalink]

### Show Tags

23 Aug 2011, 03:00
1
KUDOS
Hello,
i would solve it this way.

1. All we have now is 1 group of boys and one group of girls : so total arrangement possible is 2! = 2
and
2. Group of boys (3)can be arranged in 3! ways : so total arrangements are 3! = 6
and
3. group of girls can be arranged in 3! ways : so total arrangements are 3! = 6

so the total number of ways are 2*6*6 = 72

This type of solving is also applicable for questions that ask for arranging a couple who cannot sit seperated.

Consider giving me kudos if my explanantion was helpful.
Raghav.V
Manager
Status: Do till 740 :)
Joined: 13 Jun 2011
Posts: 113
Concentration: Strategy, General Management
GMAT 1: 460 Q35 V20
GPA: 3.6
WE: Consulting (Computer Software)
Followers: 1

Kudos [?]: 8 [0], given: 19

Re: 3 boys and 3 girls [#permalink]

### Show Tags

14 Sep 2011, 13:13
Lets assume

b1,b2,b3 g1,g2,g3

so we have this case where they cant be separated so

we have only two combinations

1) b1b2b3g1g2g3 --Arranged in 3! *3! ways = 36
2) g1g2g3b1b2b3 --Arranged in 3! *3! ways = 36

Total 72 ways
Re: 3 boys and 3 girls   [#permalink] 14 Sep 2011, 13:13
Similar topics Replies Last post
Similar
Topics:
3 Group A has 2 boys and 3 girls,group B has 3 boys and 4 girls and grou 1 25 Jun 2015, 22:24
20 5 girls and 3 boys are arranged randomly in a row 8 19 Feb 2012, 06:08
57 The ratio of boys to girls in Class A is 3 to 4. The ratio 40 03 Apr 2010, 12:57
15 From a group of 3 boys and 3 girls, 4 children are to be 18 23 Jan 2010, 00:42
9 From a group of 3 boys and 3 girls, 4 children are to be ran 10 19 Aug 2009, 09:24
Display posts from previous: Sort by