Suppose X is a binomial distribution with parameters n=100 and p = 13  then P (X= r)  is maximum when r =

P (X= r)=100Cr(23)100−r(13)r ⇒(23+13)100=(23)100[1+12]100  ⇒(n+1)|x|1+|x|=1013=33.3            ∴ r = 33