can any one explain me how we calculate no of handshakes in a group

• simple yaar nC2...if 15 people in the party they shakes hand together to each other than 15C2=105 ans
• 11 years agoHelpfull: Yes(12) No(0)
• use formula
  n(n-1)/2
  n=no. of people it will give answer..
  
• 11 years agoHelpfull: Yes(8) No(0)
• answer = n(n-1)/2
  Explain:- Suppose there are 6 people and the have to shake with every other person so to shake hand we need two hands. 1st hand is selected in 6 way and 2nd hand is selected in 5 ways. so 6*5 ways=30 ways but there is overcounting because hand shake of Sachin and rahul is same as shake hand of Rahul and Sachin so divide by 2!. therefore answer is n(n-1)/2 i.e. (6*5)/2=15 in this case.
• 11 years agoHelpfull: Yes(2) No(0)