If `((10-n)!)/((9-n)!) = 6` then `n` =

If (n)/(n+15) = 4/9 , then n = ?

Evaluate (n!)/((n-r)!) , when (i) n = 6, r = 2 (ii) n = 9, r = 5

Evaluate (n!)/((n-r)!) , when : (i) n=6, r=2 (ii) n=9, r=5

If (1)/(9!)+(1)/(10!)=(n)/(11!) , then n=121 .

If 9^(n) = (9)/(3^(n)) , the value of n is

Evaluate (n!)/((n-r)!) when (i) n=6,r=2n=9,r=5

If I_(n)=intx^(n)e^(6x)dx , then the expression 6I_(10)+10I_(9) simplifies to (where, c is the constant of integration)

In an AP,If a =-10,n=6 and a_(n)=10, then find the value of d.

If ratio of the work done by n men in (n+2) days is to the work done by n+3 men in n days is (n^(2)+2n+9):(n^(2)+3n+10), then n is equal to