Posted by **Ken** on Sunday, October 18, 2009 at 11:36pm.

Please help. Thank you

Fourteen people attend a meeting. If each person shook hands with every other person, how many handshakes were there altogether?

- maths -
**Reiny**, Sunday, October 18, 2009 at 11:47pm
In combination notation, that would be

C(14,2) = 14!/(12!2!) or 91

Or

Each of the 14 people can shake hands with 13 other people, that would be 14x13 = 182 handshakes.

But that would be all cases of A shaking with B and B shaking with A, that is, we care counting each handshake twice.

So divide the 182 by 2 to get 91

## Answer This Question

## Related Questions

- math - At the medal presentation, each person shook hands with every other ...
- Math1 - An undisclosed number of friends gather for dinner. Each person shakes ...
- Math(Please Help!) - An undisclosed number of friends gather for dinner. Each ...
- math - At a party, there were 105 handshakes. If each person shook hands exactly...
- 7th grade - At a party, there were 105 handshakes. If each person shook hands ...
- math - How many people were at a party if There were 105 handshakes at a party ...
- math - taylor was having a party.she invited 20 friends to her party, if each ...
- Math - There were 20 at a round table at dinner, each of whom shook hands with ...
- math - If 8 people went to a party and each person shook hands at least one time...
- maths - Dear Sir I need help for the below questions Please help thanks larry ...

More Related Questions