Find the last non zero digit of 96!.
a) 2 b) 4 c) 6 d) 8

• there is a technique..
  z(96/5)*z(6)
  =z(19)*z(6)
  =last digit of 19!*last digit of 6!(non zero=
  8*2=16
  so last non zero digit =6
• 11 years agoHelpfull: Yes(8) No(3)
• how?
  
  pls xplain.dnt know thw procedure..
• 11 years agoHelpfull: Yes(7) No(1)
• split the number as 5's multiple
  96=5(19)+1
  last digit of(2^19*last non zero digit of 19! * last non zero dig of 1!)
  =6
• 11 years agoHelpfull: Yes(3) No(2)
• answer is 6
  
  Z(n) denotes the last non zero digit in n!
  
  Z(n) = {4 if tens digit is odd and 6 if tens digit is even) *
  Z(n/5) * z(Units digit).
• 11 years agoHelpfull: Yes(1) No(6)
• HOWW.
  dont understand..
  
• 11 years agoHelpfull: Yes(1) No(0)
• ans will be 4
• 11 years agoHelpfull: Yes(1) No(0)
• ans is 4....
  6*d(96/5)*d(6)=6*d(13)*2
  =6*d(2)*2
  =6*2*2
  =4
• 11 years agoHelpfull: Yes(1) No(5)
• general procedure to find non zero digit in n!
  let Z(n) denotes the last non zero digit in n!
  
  Z(n) = {4 if tens digit is odd and 6 if tens digit is even) *Z(n/5) * z(Units digit).
  sol:
  Z(96) = 4 * Z(96/5) * Z(6)
  = 4 * z(19) * last non zero digit of 6!
  = 4 * last non zero digit of 19! * last non zero digit of 6!
  = 4 * 2 * last non zero digit of (720)
  {z(19)=4*z(19/5)*z(9)
  =4 * last non zero digit of 3! * last non zero digit of 9!
  =4*6*last non zero digit of (362880)
  =4*6*8
  192
  i.e. 2}
  =4*2*2
  16
  i.e. 6 is the ans :)
  
  
  = 4 * 4 * 2
  = 16 * 2
  = 32 (answer is the last digit ie 2)
  = 2
  
• 11 years agoHelpfull: Yes(1) No(1)
• answer is 6..
  
• 11 years agoHelpfull: Yes(0) No(3)
• explain clearly
• 11 years agoHelpfull: Yes(0) No(1)
• http://adityasrmca.co.cc/
• 11 years agoHelpfull: Yes(0) No(2)