[ 10 posts ]

 Print view Previous topic | Next topic

#### NP: Combinatorics Ch 3, Q5 page 53, 5th Edition

Author Message
 Post subject: NP: Combinatorics Ch 3, Q5 page 53, 5th Edition  Posted: Sat Jul 07, 2012 4:50 am
 Students

Posts: 10
 Hi, I am having trouble with the explanation to the following question in the NP guide: The New York Classical Group is designing the liner notes for an upcoming cd release. THere are 10 soloists featured on the album, but the liner notes are only 5 pages long, and therefore only have room for 5 soloists. The soloists are fighting over which of them will appear in the liner notes, though not about which page they appear on. How many different combinations of soloists can appear in the liner notes?My thinking:I thought the ans was 10*9*8*7*6/5! because the soloists are not concerned about which page they appear on so the order doesn't matter and hence we got to divide by the 5! ---->the slot method.If i follow the Anagram method i get YYYYYNNNNN ie 10!/5!5!However, the strategy guide says the order is imp and lists 2 anagrams ie 12345NNNNN as well as YYYYYNNNNNand the answer is 10!/5! 5!But if the anagram is 12345NNNNN and order is important the answer should be 10!/5!.Please let me know where I've gone wrong in my thinking.Thank you!Aliag

 Post subject: Re: NP: Combinatorics Ch 3, Q5 page 53, 5th Edition  Posted: Sat Jul 07, 2012 8:41 pm
 ManhattanGMAT Staff

Posts: 2390
 Good catch! I can see why you are confused. The answer choice is wrong when it states that the order is important. In fact, the problem tells us that the order is NOT important. In a previous version of this problem, the order was important, and that sentence is probably left over from that answer.Anyway, your method to solve is correct and matches up with the answer provided. Please just disregard that sentence about the order being important; it clearly is not. _________________Jamie NelsonManhattanGMAT Instructor

 Post subject: Re: NP: Combinatorics Ch 3, Q5 page 53, 5th Edition  Posted: Sun Jul 08, 2012 1:22 am
 Students

Posts: 10
 Thank you Jamie. So would the correction appear in the Errata section of the NP guide so that others don't get confused :)Thanks!Aliag

 Post subject: Re: NP: Combinatorics Ch 3, Q5 page 53, 5th Edition  Posted: Sun Jul 08, 2012 12:17 pm
 ManhattanGMAT Staff

Posts: 4404
Location: Southwest Airlines, seat 21C
 only if someone reports the error! go ahead and let them know at http://www.manhattangmat.com/errata.cfm _________________Tim SandersManhattan GMAT Instructor

 Post subject: Re: NP: Combinatorics Ch 3, Q5 page 53, 5th Edition  Posted: Sun Jul 08, 2012 11:07 pm
 Students

Posts: 10
 Thanks Tim, good idea, Done!I also believe I've made this post in the wrong forum. It should have been in the Math non CAT forum.

 Post subject: Re: NP: Combinatorics Ch 3, Q5 page 53, 5th Edition  Posted: Mon Jul 09, 2012 8:09 am
 ManhattanGMAT Staff

Posts: 4404
Location: Southwest Airlines, seat 21C
 that's fine; i didn't notice it either! :) _________________Tim SandersManhattan GMAT Instructor

 Post subject: Re: NP: Combinatorics Ch 3, Q5 page 53, 5th Edition  Posted: Tue Dec 18, 2012 5:11 am
 Course Students

Posts: 1
 Thanks aliag916 and Tim.I went through the same confusion and it got resolved after reading this post.So Tim, since the order is not important, we can use 10C5 right?Coz that's what I've used and it comes up to be same as aliag916's answer.Just needed confirmation on the use of 10C5 here.Cheers,Taz

 Post subject: Re: NP: Combinatorics Ch 3, Q5 page 53, 5th Edition  Posted: Sat Dec 22, 2012 12:31 am
 ManhattanGMAT Staff

Posts: 706
 tabishsangrar wrote:Thanks aliag916 and Tim.I went through the same confusion and it got resolved after reading this post.So Tim, since the order is not important, we can use 10C5 right?Coz that's what I've used and it comes up to be same as aliag916's answer.Just needed confirmation on the use of 10C5 here.Cheers,TazCorrect. 10C5 or 10!/5!5! is the correct formula here. Glad that these forums serve as an errata for our students! _________________Joe LuceroManhattan GMAT Instructor

 Post subject: Re: NP: Combinatorics Ch 3, Q5 page 53, 5th Edition  Posted: Thu Jan 03, 2013 11:28 pm
 Forum Guests

Posts: 16
 aliag916 wrote:The New York Classical Group is designing the liner notes for an upcoming cd release. THere are 10 soloists featured on the album, but the liner notes are only 5 pages long, and therefore only have room for 5 soloists. The soloists are fighting over which of them will appear in the liner notes, though not about which page they appear on. How many different combinations of soloists can appear in the liner notes?Oh! So these things happen! :) 10!/5!5! it is!

 Post subject: Re: NP: Combinatorics Ch 3, Q5 page 53, 5th Edition  Posted: Thu Jan 03, 2013 11:52 pm
 ManhattanGMAT Staff

Posts: 4404
Location: Southwest Airlines, seat 21C
 :) _________________Tim SandersManhattan GMAT Instructor

Display posts from previous:  Sort by

[ 10 posts ]

#### Who is online

 Users browsing this forum: No registered users and 0 guests

 You cannot post new topics in this forumYou cannot reply to topics in this forumYou cannot edit your posts in this forumYou cannot delete your posts in this forumYou cannot post attachments in this forum

Search for:
 Jump to:  Select a forum ------------------ Ask An Instructor    General GMAT Strategy Questions    GMAT Math       General Math Questions       GMAT Prep Math       Manhattan GMAT CAT Math       Manhattan GMAT Non-CAT Math       Official Guide Math    GMAT Verbal       General Verbal Questions       GMAT Prep Verbal       Manhattan GMAT CAT Verbal       Manhattan GMAT Non-CAT Verbal       Official Guide Verbal    GMAT Integrated Reasoning (IR)       GMAT Prep IR       Manhattan GMAT CAT IR       Manhattan GMAT Non-CAT IR    GMAT AWA Essays Manhattan GMAT    Ask Student Services    Study Groups    GMAT Test Day    Test Centers    Instructor Feedback    Course Feedback B-School    Ask an mbaMission Admissions Consultant    B-School Essays    Business Schools    Professional Networking