xxMsJojoxx
Junior Member
- Joined
- Oct 6, 2020
- Messages
- 54
Hi,
Re: the formula to calculate variance is as followed, as taught in our Intro to Stats Course:


I'm not understand how the general variance formula relates to the below variance formula, for binomial random variable?

whereby n = # of trails, and [=probability of succcess
I tried to break it down as followed:
'p' is the probability, which is P(X=x).
But how does 'np' equate to (x-E(X))^2?
Re: the formula to calculate variance is as followed, as taught in our Intro to Stats Course:

I'm not understand how the general variance formula relates to the below variance formula, for binomial random variable?
whereby n = # of trails, and [=probability of succcess
I tried to break it down as followed:
'p' is the probability, which is P(X=x).
But how does 'np' equate to (x-E(X))^2?