10 people are there, they are shaking hands together, how many hand shakes possible, if they are in no pair of cyclic sequence.
a) 45
b) 9
c) 12
d) 10

• a)45
  1st person shakes hand with 9 others=9 handshakes
  then 2nd person shakes hand with 8 others(ie excluding 1st person)=8 handshakes
  ....
  finally 9th person=1 hanshake and 10th person=0 handshake
  so total=9+8+7+6+5+4+3+2+1=45 handshakes
• 13 years agoHelpfull: Yes(66) No(9)
• 10C2=45
  ans. a
• 13 years agoHelpfull: Yes(24) No(4)
• there is no form cyclic sequence,so ans is n-1
  that is 10-1=9
  Option(b)
• 13 years agoHelpfull: Yes(18) No(25)
• Answer should be b.)9 as people are shaking hands "together" simultaneously and not one after other.
• 12 years agoHelpfull: Yes(10) No(3)
• 10C2= 10*9/1*2 =45.So option A) is correct
• 13 years agoHelpfull: Yes(8) No(3)
• when there is no cyclic sequence then sloution can be given as
  10c2=45;
  so total=9+8+7+6+5+4+3+2+1=45 handshakes
• 13 years agoHelpfull: Yes(6) No(1)
• Handshakes are given in linear manner =n-1(last person cannot give hand shake to first person)
  Handshakes are given in cyclic manner =n(last person can give hand shake to first person)
• 13 years agoHelpfull: Yes(5) No(4)
• the question clearly mentions about no cyclic sequence.So the ans is 9.Formula is n-1. those who have mentioned it has 45 u must look into the question properly that they have not said u must shake hands with every persons atleast once.
• 9 years agoHelpfull: Yes(5) No(0)
• 10c2= n!/(n-r)!.r!
  =10!/8!.2!
  =10*9/2
  =45
  
• 12 years agoHelpfull: Yes(3) No(1)
• no pair of cyclic sequence means(n-1)
  pair of cyclic sequence means n
  so here 10-1=9
• 11 years agoHelpfull: Yes(2) No(2)
• i think if 1 person shake hand with 9 people ,than as 2 person shake hand with 3 person there is cycle between 1 , 2 ,3 as in hand shake 2 person involve and 1 person already shake hand with 2 ,3 person so when 2 person shake hand with 3 cycle occurs....answer is 9 according to me
  
• 12 years agoHelpfull: Yes(1) No(1)
• When A shake with B then ...always =>
  
  A*(A-1)/2
  
  10*9/2=45 Ans.
• 7 years agoHelpfull: Yes(0) No(0)
• At least 2 persons are required to shake hands... So 10c2 = 45ans.
• 7 years agoHelpfull: Yes(0) No(0)
• b)9
  because the last person cannot shake his hand to the 1st person as there should be no cycle
• 7 years agoHelpfull: Yes(0) No(0)