brain teasers

[Pitiless Wanderer]

If three individuals are in a group, how many channels of communication are there? There are six:

Call them person A, B and C

A-C
A-B
B-C
A- B,C
B- A,C
C- A,B

How many channels of communication in a group with seven people?

 

[Frosties]

28?

EDIT: In case I'm right, here's what I did:

7+6+5+4+3+2+1

 

[Pitiless Wanderer]

you're way off

 

[refraction]

7! so 5040

 

[TomAwesome]

364?

7! would be the number of different ways to order the numbers 1 through 7.

 

[refraction]

Oh right. Hungover math ftw.