Question

What are the mean and standard deviation of a binomial probability distribution with `n=12` and `p=3/5`?

Answer 1

Mean is `7.2` and standard deviation is `1.697`

Explanation:

Mean of a binomial probability distribution is given by `np` and standard deviation is given by `sqrtnpq`, where `q=1-p`.

In the given example, `np=12*3/5=7.2`,

As `q=1-3/5=2/5`, `sqrtnpq=sqrt(12*3/5*2/5)=1/5*sqrt72=6sqrt2/5=1.697`

Hence mean is `7.2` and standard deviation is `1.697`