# Math Help - binomial distribution:quick help

1. ## binomial distribution:quick help

hey i just need some help with this question: im confused about the formula. find sigma and mu

A)the probability distribution of the # of tails obtained in 3 flips of a fair coin.
and

B) the # of tails obtained in 1600 flips of a coin.

2. Originally Posted by rafaeli
hey i just need some help with this question: im confused about the formula. find sigma and mu

A)the probability distribution of the # of tails obtained in 3 flips of a fair coin.
and

B) the # of tails obtained in 1600 flips of a coin.

$\mu = n\times p$

$\sigma = \sqrt{n\times p \times (1-p)}$

where n = number of trials (tosses)

In the first question n = 3 in the second n = 1600

and p = probability of success. In your case $p = \frac{1}{2}$