Seven people meet and shake hands with one another. How many handshakes occur ?

Answer 1

Start thinking about it this way: the first person can shake hands with the other 6 people, none of whom have already shaken hands with him. The second person only has 5 other people to shake hands with. Keep thinking like this and you'll find your own answer rather than getting us to do do your homework for you!

Answer 2

6 + 5 + 4 + 3 + 2 + 1

Answer 3

The combination of seven people by two is:

C = 7*6/1*2 = 21

Answer 4

21

Answer 5

42 handshakes. There are 7 people and they shake hands with 6 other people. They can't shake their own hands. So it would be 7x6=42

Answer 6

think about it this way, the first shakes hands with 6 other people(unless he shakes his own hand lol), same for the second and so on : so it's 7*6 = 42 times

or it's 7C2 = 42 :D

Answer 7

49

Answer 8

Combination Formula
n = 7 people
r = 2 people are needed to make a handshake.

nCr = (n!)/(r!(n - r)!)

7C2 = (7!)/(2!(7 - 2)!)
7C2 = (7!)/(2! * 5!)
7C2 = (7 * 6 * 5 * 4 * 3 * 2 * 1)/(2 * 1 * 5 * 4 * 3 * 2 * 1)
7C2 = (7 * 6)/(2 * 1)
7C2 = 7 * 3
7C2 = 21

Answer 9

7(7+1)/2 = 28, unless some get perverse & shake hands more than once.

Answer 10

SEE, SEVENTH WILL SHAKE HAND WITH 6 PEOPLE . NOW REMAINING WILL NOT SHAKE HAND WITH THE SEVENTH I.E. 6 SHAKEHANDS TILL NOW. NOW THE 6TH WILL SHAKE HANDS WITH REST 5 . THE REST WILL NOW NOT SHAKE HANDS WITH THE 6TH AND SO ON ......................
SO ANSWER IS
6+5+4+3+2+1 = 21