The p.m.f. of a random variable X is $$\mathrm{P(X = x) = {1 \over {{2^5}}}\left( {_x^5} \right),x = 0,1,2,3,4,5}=0$$ then

The variance of the following probability distribution is,

If the sum of mean and variance of a binomial distribution for 5 trials is 1.8, then probability of a success is

Two unbiased dice are thrown. Then the probability that neither a doublet nor a total of 10 will appear is