Hi,

Suppose there are 6 people in a room. Each of those 6 would shake hands with 5 others. 

Thus, we have 6 * 5. However, there would be handshakes between each pair twice. 

we must divide by two, giving us the formula: 

6*5/2 or, generalized to n(n-1)/2.



___1___2___3__4__5__6

1|1,1 1,2  1,3 etc

2|2,1 etc

3|3,1 _etc

4|

5|



 

RELATED QUESTIONS

If 20 people in a class shake hands with each other exactly once, how many handshakes... (answered by Edwin McCravy)

1 - How many handshakes can take place if there are 100 people and no one shakes hands... (answered by khwang)

If seven matrons assembled for a meeting shake hands with one another,how many handshakes  (answered by stanbon)

If seven matrons assembled for a meeting shake hands with one another,how many handshakes  (answered by josgarithmetic,KMST)

Seven matrons assembled for a meeting,shake hands with one another. How many handshakes... (answered by stanbon,richwmiller)

In a party 15 people shake their hands with each other. How many times did the hand-shake  (answered by solver91311)

i have invited nine people to a party. They all shake hands with me, and each pair shake... (answered by ikleyn)

The 8 people at a party shook hands exactly once with each of the others before the 9th... (answered by AnlytcPhil,fractalier)

25 team members shake hands. how many handshakes take place?hint look at the pattern... (answered by stanbon)