Wednesday

April 1, 2015

April 1, 2015

Posted by **donna** on Thursday, April 22, 2010 at 10:56pm.

- math -
**Reiny**, Thursday, April 22, 2010 at 11:00pmfor n people there will be C(n,2) handshakes

C(n,2) = 105

n!/(2!(n-2)!) = 105

n(n-1)/2 = 105

n^2 - n - 210 = 0

(n-15(n+14) = 0

n = 15 or n=-14, but n > 0

so there were 15 people

**Answer this Question**

**Related Questions**

math - How many people were at a party if There were 105 handshakes at a party ...

7th grade - At a party, there were 105 handshakes. If each person shook hands ...

math - taylor was having a party.she invited 20 friends to her party, if each ...

math - At a party everyone shook hands with everyone exactly once there were a ...

Algebra - A scientist wants to research the potential spread of germs by contact...

maths - Please help. Thank you Fourteen people attend a meeting. If each person ...

Math - At a party, 55 handshakes took place as everyone shook hands with ...

Math - At a party, 55 handshakes took place as everyone 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 ...