20 men shake hands with each other. Maximum no of handshakes without cyclic handshakes.

• 1st person will shake hand with 19 people
  2nd person will shake hand with 18 people
  3rd person will shake hand with 17 people
  ......
  
  total no. of handshakes = 19+18+17+...+3+2+1 = 19*(19+1)/2 = 190
  
  
  or, if there are n persons then no. of shakehands = nC2 = 20C2 = 190
• 10 years agoHelpfull: Yes(53) No(7)
• 190
  
  no of handshakes = 19+18+17+...+2+1
  = 19*20/2 ==>[sum of n numbers = n(n+1)/2]
  = 190
• 10 years agoHelpfull: Yes(8) No(0)
• Maximum number of handshakes=nc2
  if there are n peoples
  so 20c2 handshakes.
• 10 years agoHelpfull: Yes(7) No(0)
• No. of handshakes ll = n(n-1)/2
  
  = 20 (19)/2
  
  =190 handshakes
• 10 years agoHelpfull: Yes(6) No(1)
• (20*19)/2=190
  e.g-let there was 5 people,we hv to find total no. of handshake,so
  starting from 1st person,he shook hand wid 4 other people,and completed his turn,so total no. of h.s-4,now come to 2nd person ,he shook with other 3 people and completed his turn,so in this case total no of H.S-3,now come to the 3rd person,he does the same,so total no. of H.S-2,now the 4th have only 1 choice.
  here summing all the above we get---4+3+2+1=10((5*4)/2).
  we can try it wid othr e.g.
• 10 years agoHelpfull: Yes(3) No(0)
• the ans is 20C2 =100
  
• 9 years agoHelpfull: Yes(2) No(0)
• 190
  
  1st person shake hand with 19 people
  2nd person shake hand with 18 people
  .
  .
  .
  .
  total=19+18+17+.............+1=n(n+1)/2
  (19*20)/2=19*10=190
  
• 10 years agoHelpfull: Yes(1) No(0)
• 19+18+17+16+15+14+13+12+11+10+9+8+7+6+5+4+3+2+1=190
• 10 years agoHelpfull: Yes(1) No(0)
• its a simple quation of combunation
  20C2 = !20/!18*!2 = 190
• 9 years agoHelpfull: Yes(1) No(0)
• vikas
  If there are n number of people then total number of handshakes are
  n(n-1)/2
  20*19/2=190
• 9 years agoHelpfull: Yes(1) No(0)
• n(n-1)/2=20(20-1)/2
  20*19/2=190
• 9 years agoHelpfull: Yes(1) No(0)
• 20 men can shake hands only with 19 men.hence n*(n-1)/2= 20*19/2=190
• 9 years agoHelpfull: Yes(1) No(0)
• 19.........for not forming cycle it needs 1 less men
  
• 9 years agoHelpfull: Yes(1) No(1)
• If there are n number of people then total number of handshakes are
  n(n-1)/2
  20*19/2=190
• 10 years agoHelpfull: Yes(0) No(1)
• n(n-1)/2=(20*(19))/2=380
• 9 years agoHelpfull: Yes(0) No(2)
• maximum no of handshakes=n(n-1)/2
  20*19/2
  answer is 190...
• 9 years agoHelpfull: Yes(0) No(0)
• 20c2 handshakes without cyclic is 190 handshakes
  
• 9 years agoHelpfull: Yes(0) No(0)
• 10 men can shake hands with only 10 people , when they are shaking hands with each other. ( without cyclic handshakes)
  
• 9 years agoHelpfull: Yes(0) No(0)
• 1st person will shake hand with 19 people
  2nd person will shake hand with 18 people
  3rd person will shake hand with 17 people
  ......
  
  total no. of handshakes = 19+18+17+...+3+2+1 = 19*(19+1)/2 = 190
  
  
  or, if there are n persons then no. of shakehands = nC2 = 20C2 = 190
• 8 years agoHelpfull: Yes(0) No(0)