How many distinct groupings of 2 tribes are possible?

Expert replies

Vemuri: Legendary Member; Posts: 682; Joined: Fri Jan 16, 2009 2:40 amFollowed by: 1 member; Thanked: 32 times

by Vemuri » Sun Mar 22, 2009 5:59 am

Ten telegenic contestants with a variety of personality disorders are to be divided into 2 tribes of 5 members each, tribe A and tribe B, for a competition. How many distinct groupings of 2 tribes are possible?

A. 120
B. 126
C. 252
D. 1200
E. 1260

Like this post

Source: Beat The GMAT — Problem Solving | Sun Mar 22, 2009 5:59 am

GMAT/MBA Expert

Brent@GMATPrepNow: GMAT Instructor; Posts: 16207; Joined: Mon Dec 08, 2008 6:26 pmFollowed by: 1268 members; Location: Vancouver, BC; Thanked: 5254 times; GMAT Score:770

Re: How many distinct groupings of 2 tribes are possible?

by Brent@GMATPrepNow » Sun Mar 22, 2009 6:45 am

Vemuri wrote:Ten telegenic contestants with a variety of personality disorders are to be divided into 2 tribes of 5 members each, tribe A and tribe B, for a competition. How many distinct groupings of 2 tribes are possible?

A. 120
B. 126
C. 252
D. 1200
E. 1260

We can break this task into two stages:
1. Choose 5 contestants and place them in Tribe A
2. Place the remaining 5 contestants in Tribe B

We can accomplish stage A in 10C5 ways (252)
Stage B is accomplished in 1 way
The total number is 252x1=252 (C)

Brent Hanneson - Creator of GMATPrepNow.com

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

560 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (560 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review