It is currently 18 Nov 2017, 03:41

### 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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# There are 2 brothers among a group of 20 persons. In how

 post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
CEO
Joined: 15 Aug 2003
Posts: 3452

Kudos [?]: 924 [0], given: 781

There are 2 brothers among a group of 20 persons. In how [#permalink]

### Show Tags

07 Oct 2003, 20:11
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 100% (00:01) wrong based on 0 sessions

### HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

There are 2 brothers among a group of 20 persons. In how many ways can the group be arranged around a circle so that there is exactly one person between the two brothers?

1) 2 * 19!
2) 18! * 18
3) 19! * 18
4) 2 * 18!

Kudos [?]: 924 [0], given: 781

SVP
Joined: 03 Feb 2003
Posts: 1603

Kudos [?]: 308 [0], given: 0

### Show Tags

07 Oct 2003, 23:28
fix one person and the brothers B1 P B2 = 2 ways to do so.
other 17 people= 17!
Each person out of 18 can be fixed between the two=18

thus, 2*17!*18=2*18!

Kudos [?]: 308 [0], given: 0

SVP
Joined: 30 Oct 2003
Posts: 1788

Kudos [?]: 114 [0], given: 0

Location: NewJersey USA

### Show Tags

08 Jan 2004, 10:40
Fix the postion of two brothers. This leaves us with 18 people.
So there 18 ways in which a person can sit between two brother. Now swap thsoe bothers we get another 18 ways
So combinations = 2 * 18.
Consider the groupe of three people a single entity
we have another 17 people left so there are 18 entities to be arranged
Around a circle. Tis can be done in (18-1)! = 17!

Total no of ways = 2 * 18 * 17! = 2 * 18!

Kudos [?]: 114 [0], given: 0

08 Jan 2004, 10:40
Display posts from previous: Sort by

# There are 2 brothers among a group of 20 persons. In how

 post reply Question banks Downloads My Bookmarks Reviews Important topics

 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®.