The mean and variance of a binomial distribution are 8 and 4 respectively. Then P(X=1) is equal to
The height of persons in a country is a random variable of the type
E(X−k)2 is minimum when
Var(2X± 3) if Var(X)=1 is
For two random variables X and Y, the relation E(XY)=E(X)E(Y) holds good
If P1 (x) and P2 (x) be the marginal probability functions of two independent discrete random variables X and Y, then their joint probability function P(x,y)=