There is 7 friends (A1,A2,A3....A7).If A1 have to have shake with all with out repeat. How many hand shakes possible?

• 6 is the answerrrrr
• 13 years agoHelpfull: Yes(18) No(2)
• 6........
  a1 can shake hands with A2,A3,A4,A5,A6&A7
• 13 years agoHelpfull: Yes(6) No(2)
• The ans is 21.....
  reason being 1st person will shake hand with 6 others
  similary 2 will hand shake with 5 thus 6+5+4+3+2+1=21
• 13 years agoHelpfull: Yes(6) No(10)
• ans:21
  7(7-1)/2
  
• 13 years agoHelpfull: Yes(5) No(14)
• ans 6.... A1A2 A1A3 A1A4 A1A5 A1A6 A1A7 NO REPETATION
• 13 years agoHelpfull: Yes(5) No(3)
• i duno how to derive answer for this problem
  i just calculated b use of calculater
  ans i got is 3.1035*10^64
• 13 years agoHelpfull: Yes(0) No(6)