If `12 P_r=11 P_6+6*11 P_5` then `r` is equal to

If 12P_(r)=11P_(6)+6.11P_(5) then r is equal to

If "^12P_r = "^11P_6 + 6 . "^11P_5 then r is equal to

If^(12)P, = ^(11)P_(6)+6.^(11)P_(5), then r is equal to

If P(12,r)=P(11,6)+6.P(11,5) then r=

if nP_(r)=720nC_(r), the value of r and the no.of six digit no.all digits which are odd is,and if 12P_(r)=11P_(6)+2*11P_(5),r=? and if 35C_(n+7)=35C_(4n-2) then n is equals to: