Question

What are the mean and standard deviation of a binomial probability distribution with `n=12` and `p=7/60`?

Answer 1

Mean is `1.4` and Standard Deviation is `1.112`

Explanation:

The mean and standard deviation of a binomial probability distribution are `np` and `sqrt(npq)` respectively where `n` is number of tria;ls and `p` is probability of success of the event. Here `q=1-p`, and is the probability of failure of the event.

With `n=12` and `p=7/60`, `q=1-7/60=53/60`.

Hence mean is `12xx7/60=7/5=1.4` and

Standard Deviation is `sqrt(12xx7/60xx53/60)=(1/60)sqrt(7xx12xx53)`

= `sqrt4452/60=66.7233/60=1.112`