# Probability distribution help

1. Jul 24, 2004

### doc_doc

hello,
please i'm, taking statistic this term and i really have a problem with this question:
which is
for the distribution B(3,0.5),
a) how many outcomes are there to each trial?
b) how many trials are there?
c) how many possible values can the variable take?
d) what are the mean and standard daviations of this distribution?
i'm beggining you
thanks alot
jody

2. Jul 24, 2004

### theFuture

I assume you are talking about a binomial distribuition for n=3 and p=.5? Think about what a binomial distribution is. It counts the number of sucesses in n independent bernoulli trials that have sucess with probability p, right?

a) Well, what are the outcomes of a bernoulli trial?
b) Well, what is n?
c) Think about the sample space, how many possible successes can you get in n trials?
d)Well, the mean is the expectation and the SD is the root of the variance.

That should get you started.