Question

How can you use normal distribution to approximate the binomial distribution?

Answer 1

`N(np, sqrt(np(1-p)))`

Explanation:

`n = "number of experiments"`
`p = "probability for success in a single experiment"`
`"Then you take"`
`m = n p = "mean of the normal distribution"`
`s = sqrt(np(1-p)) = "standard deviation of the normal distr."`
`"So we have"`
`N(np, sqrt(np(1-p)))`
`"The approximation will only be good for"`
`np > 5 or n(1-p) > 5`
`"so it is very good for p around 0.5 and big n."`