Question

What are the mean and standard deviation of a binomial probability distribution with `n=169` and `p=1/13`?

Answer 1

Mean is `13` and standard deviation is `3.464`.

Explanation:

Mean and standard deviation of a binomial probability distribution are given by `np` and `sqrt(npq)` where `q=1-p`.

In the given distribution, `n=169` and `p=1/13`. hence `q=1-p=1-1/13=12/13`.

Hence, mean is `169*1/13` i.e. `13` and standard deviation is `sqrt(169*(1/13)*(12/13))` or `sqrt12=3.464`.