if nc5=nc6 what is value of n

• n!/((n-5)!5!)=n!/((n-6)!6!)
  n-5=6
  n=11
  So, the answer is 11.
• 8 years agoHelpfull: Yes(6) No(0)
• Hi,
  There is a rule in combinations i..e nCr=nC(n-r), just check out the given question,nC5=NC6 that means r=5 and n-r=6 ...substituting r=5 in the second equation n-5=6,or n=11.
  Hence the answer must be 11
• 8 years agoHelpfull: Yes(5) No(0)
• Nc5=nc6
  n/(n-5)*5= n/(n-6)*6
  To solve this
  n(6n-36)= n(5n-25)
  6n^2-36= 5n^2-25
  n^2-36n+ 25n=0
  N^2-11n=0
  n=11
  Ans=11
• 8 years agoHelpfull: Yes(3) No(0)
• from the basic formula
  ncr=nc(n-r)--------(1)
  Given nc5=nc6------------(2)
  by comparing (1)&(2)
  r=5;n-r=6;
  n-r=6; by substituting r=5
  n-5=6;
  n=6+5==>11;
  
• 8 years agoHelpfull: Yes(3) No(0)
• nC5=nC6 the value of n is always = 5+6=11
  
• 8 years agoHelpfull: Yes(3) No(1)
• nc5=nc6
  n!/(n-5)!*5!=n!/(n-6)*6!
  on solving this
  1/5!=(n-5)/6!
  1/120=(n-5)/720
  720=120n-600
  720+600=120n
  1320/120=n
  n=11
• 8 years agoHelpfull: Yes(2) No(0)
• ncp=ncq
  P+q=n
  nc5=nc6
  n=5+6
  n=11
• 6 years agoHelpfull: Yes(2) No(0)
• n-6
  n!/n!(n-5)!=n!/n!(n-6)!
  on simplification we arrive at ans:n-6
• 8 years agoHelpfull: Yes(1) No(4)