I have two formulas for the mean and variance of binomial distribution, the success with probability p and failure with probability 1-p
It says on what I have been given that the mean and variance for the number of successes in n trials are given by:
mean = n x p:
variance = n x p x (1-p)
Is this for both successes and failures as above it just says successes in n trials so I am just a bit confused.
Thanks