If `P(11 , r)=P(12 , r-1)` find `ndot`

If P(5, r)=2.P(6, r-1), find r.

If P(5, r)=P(6, r-1) ,find r.

If P(5,r)=2,P(6,r-1), find r

Find r if : P(11,r) = P(12,r-1)

If ""^(12)P_(r)=1320 , find r.

If 7.5p_(r)=7p_(r-1) then find r

If 7.5p_(r)=7p_(r-1) ,then find r

If "^(n+5)P_(n+1) = (11(n-1))/2"^(n+3)P_n , find ndot

Iff ""^(5)P_(r)=""^(6)P_(r-1) find r.

(i) If ""^(5)P_(r)=2xx""^(6)P_(r-1) , find r. (ii) If ""^(20)P_(r)=13xx""^(20)P_(r-1) , find r. (iii) If ""^(11)P_(r)=""^(12)P_(r-1) , find r.