Q5 of 30 Page 13

If the mean and variance of a binomial distribution are respectively 9 and 6, find the distribution.

Let X denote the variance with parameters n and p


p + q = 1 ⇒ q = 1 - p


Given, mean = np = 9 and variance = npq = 6


npq = 6


⇒9q = 6





Now, np = 9



⇒ n = 27



The required binomial distribution is given by,


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