+0  
 
0
405
1
avatar

In how many ways can friends sit at a dinner table if two of them, Anna and Bob, insist on having exactly two people seated between them? (As usual, two seatings are considered the same if one is a rotation of the other.)

Guest Jun 13, 2017
 #1
avatar+92465 
+1

 

Assuming that there are  "n"  total  people

 

Anchor Anna and Bob in any two chairs separated by two people.....then the other people can be arranged in (n - 2)! ways

 

And Anna and Bob  themselves can be arranged in 2 ways

 

So.....the total number of arrangements  =   2 * ( n - 2)!   ways

 

 

cool cool cool

CPhill  Jun 13, 2017
edited by CPhill  Jun 13, 2017
edited by CPhill  Jun 13, 2017
edited by CPhill  Jun 13, 2017

31 Online Users

avatar
avatar
avatar

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.