It is currently 20 Oct 2017, 21:00

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

In how many ways can five girls stand in line if Maggie and Lisa canno

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

Hide Tags

Manager
Manager
User avatar
Joined: 19 Feb 2009
Posts: 54

Kudos [?]: 131 [0], given: 8

Schools: INSEAD,Nanyang Business school, CBS,
In how many ways can five girls stand in line if Maggie and Lisa canno [#permalink]

Show Tags

New post 05 Feb 2010, 13:18
00:00
A
B
C
D
E

Difficulty:

  55% (hard)

Question Stats:

58% (00:45) correct 42% (00:55) wrong based on 65 sessions

HideShow timer Statistics

In how many ways can five girls stand in line if Maggie and Lisa cannot stand next to each other?

(A) 112
(B) 96
(C) 84
(D) 72
(E) 60
[Reveal] Spoiler: OA

_________________

Working without expecting fruit helps in mastering the art of doing fault-free action !

Kudos [?]: 131 [0], given: 8

Expert Post
1 KUDOS received
CEO
CEO
User avatar
Joined: 17 Nov 2007
Posts: 3584

Kudos [?]: 4586 [1], given: 360

Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40
GMAT ToolKit User Premium Member
Re: In how many ways can five girls stand in line if Maggie and Lisa canno [#permalink]

Show Tags

New post 05 Feb 2010, 13:31
1
This post received
KUDOS
Expert's post
1. the total number of permutations: 5! = 120
2. Let's consider Maggie and Lisa as one object, then the total number of permutations with Maggie and Lisa together: 4! = 24.
3. Take into account that [Maggie, Lisa] and [Lisa, Maggie] are different.
4. Maggie and Lisa cannot stand next to each other in: 120 - 2*24 = 72 ways.
_________________

HOT! GMAT TOOLKIT 2 (iOS) / GMAT TOOLKIT (Android) - The OFFICIAL GMAT CLUB PREP APP, a must-have app especially if you aim at 700+ | PrepGame

Kudos [?]: 4586 [1], given: 360

Manager
Manager
User avatar
Joined: 19 Feb 2009
Posts: 54

Kudos [?]: 131 [0], given: 8

Schools: INSEAD,Nanyang Business school, CBS,
Re: In how many ways can five girls stand in line if Maggie and Lisa canno [#permalink]

Show Tags

New post 05 Feb 2010, 13:52
Got it walker..

Thanks V.Much for this explanation
_________________

Working without expecting fruit helps in mastering the art of doing fault-free action !

Kudos [?]: 131 [0], given: 8

Intern
Intern
User avatar
Joined: 05 Nov 2014
Posts: 42

Kudos [?]: 79 [0], given: 15

Concentration: Marketing, International Business
Re: In how many ways can five girls stand in line if Maggie and Lisa canno [#permalink]

Show Tags

New post 27 Jul 2015, 00:09
can we solve this with \(P^n_r\) formula?
_________________

Kudos = Thanks

"Yeah, you can get a nickel for boosting Starfall, but jacking Heal's a ten-day stint in county.
Now lifting Faerie Fire, they just let you go for that — it's not even worth the paperwork.
But Reincarnation, man! That'll get you life!"

Kudos [?]: 79 [0], given: 15

Expert Post
SVP
SVP
User avatar
G
Joined: 08 Jul 2010
Posts: 1835

Kudos [?]: 2279 [0], given: 51

Location: India
GMAT: INSIGHT
WE: Education (Education)
Reviews Badge
Re: In how many ways can five girls stand in line if Maggie and Lisa canno [#permalink]

Show Tags

New post 27 Jul 2015, 01:19
Subanta wrote:
can we solve this with \(P^n_r\) formula?


Jut a personal Suggestion: It's best to see the steps and work in steps in P&C problems rather than being dependent on formulas

However, Answer to your query is as follows

Quote:
In how many ways can five girls stand in line if Maggie and Lisa cannot stand next to each other?

(A) 112
(B) 96
(C) 84
(D) 72
(E) 60


5 girls can stand in line in \(P^5_5 = 120 ways\)

5 girls can stand in line in such that Maggie and Lisa stand together in \(P^4_4 * P^2_2= 48 ways\)

Total favourable ways of arrangement of five girls such that Maggie and Lisa cannot stand next to each other = 120 - 48 = 72 ways

Answer: option D
_________________

Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION

Kudos [?]: 2279 [0], given: 51

Manager
Manager
User avatar
Joined: 08 Jul 2012
Posts: 50

Kudos [?]: 15 [0], given: 15

Re: In how many ways can five girls stand in line if Maggie and Lisa canno [#permalink]

Show Tags

New post 27 Jul 2015, 02:03
amod243 wrote:
In how many ways can five girls stand in line if Maggie and Lisa cannot stand next to each other?

(A) 112
(B) 96
(C) 84
(D) 72
(E) 60



Total ways (w/o restriction) 5 girls can be arranged in 5! ways = 120

Total ways in which Maggie and Lisa cannot stand next to each other = Total ways - total ways in which Maggie and Lisa stand next to each other

= 120 - (4!*2) = 120 - 48 = 72 ways.

Ans. D, 72
_________________

Our greatest weakness lies in giving up. The most certain way to succeed is always to try just one more time. - Thomas A. Edison

Kudos [?]: 15 [0], given: 15

Intern
Intern
User avatar
Joined: 05 Nov 2014
Posts: 42

Kudos [?]: 79 [0], given: 15

Concentration: Marketing, International Business
Re: In how many ways can five girls stand in line if Maggie and Lisa canno [#permalink]

Show Tags

New post 27 Jul 2015, 05:42
GMATinsight wrote:
Subanta wrote:
can we solve this with \(P^n_r\) formula?


Jut a personal Suggestion: It's best to see the steps and work in steps in P&C problems rather than being dependent on formulas

However, Answer to your query is as follows

Quote:
In how many ways can five girls stand in line if Maggie and Lisa cannot stand next to each other?

(A) 112
(B) 96
(C) 84
(D) 72
(E) 60


5 girls can stand in line in \(P^5_5 = 120 ways\)

5 girls can stand in line in such that Maggie and Lisa stand together in \(P^4_4 * P^2_2= 48 ways\)

Total favourable ways of arrangement of five girls such that Maggie and Lisa cannot stand next to each other = 120 - 48 = 72 ways

Answer: option D


Thanks. I usually solve my problems without the formulae, but I have come across many problems where it is easier to use the formulae. I'm only trying to get familiar with the usage of the formulae.
_________________

Kudos = Thanks

"Yeah, you can get a nickel for boosting Starfall, but jacking Heal's a ten-day stint in county.
Now lifting Faerie Fire, they just let you go for that — it's not even worth the paperwork.
But Reincarnation, man! That'll get you life!"

Kudos [?]: 79 [0], given: 15

Senior Manager
Senior Manager
User avatar
B
Joined: 28 Jun 2015
Posts: 300

Kudos [?]: 107 [0], given: 47

Concentration: Finance
GPA: 3.5
Re: In how many ways can five girls stand in line if Maggie and Lisa canno [#permalink]

Show Tags

New post 27 Jul 2015, 05:46
Five girls can stand in a line in 5! = 120 ways.

Let M(Maggie) and L(Lisa) be treated as a single person ML. Now, ML can be placed in -x-x-x- any one of the 4 empty slots in 4! = 24 ways. ML can be ordered between themselves in 2! ways. So, the number of ways ML can stand together = 24 * 2 = 48.

So, the number of ways they don't stand together is 120 - 48 = 72 ways. Ans (D).
_________________

I used to think the brain was the most important organ. Then I thought, look what’s telling me that.

Kudos [?]: 107 [0], given: 47

Director
Director
User avatar
G
Joined: 23 Jan 2013
Posts: 601

Kudos [?]: 22 [0], given: 41

Schools: Cambridge'16
Re: In how many ways can five girls stand in line if Maggie and Lisa canno [#permalink]

Show Tags

New post 22 Aug 2015, 21:57
Glue method (Maggie and Lisa stand together)

5!-(4!*2)=72

D

Kudos [?]: 22 [0], given: 41

Re: In how many ways can five girls stand in line if Maggie and Lisa canno   [#permalink] 22 Aug 2015, 21:57
Display posts from previous: Sort by

In how many ways can five girls stand in line if Maggie and Lisa canno

  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®.