SOLUTION: If 16 people are in a room and they shake hand with everyone else in the room Once, how many hands will be shaken? (bob shaking hands with fred is the same as fred shaking hands bo

Question 470814: If 16 people are in a room and they shake hand with everyone else in the room Once, how many hands will be shaken? (bob shaking hands with fred is the same as fred shaking hands bob)
I know you should use a basic counting theory. my first thought is 16x16.
I could figure it out if I knew what formula I should use.
Answer by sudhanshu_kmr(1152) (Show Source): You can put this solution on YOUR website!

It is problem of combination.
Number of ways to select 2 out of n.
nC2 = n!/[2!*(n-2)!]

solution = 16C2 = 120

if any doubt, you are welcome to contact me..sudhanshu.cochin@gmail.com
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