Question

If for a binomial distribution with n = 16, the ratio of mean to variance is $\frac{5}{4}$, then the probability of success is

• A. $\frac{4}{5}$
• B. $\frac{2}{3}$
• C. $\frac{1}{5}$
• D. $\frac{1}{4}$

Answer 1

The correct option is C $\frac{1}{5}$

The ratio of mean to variance will be
$\frac{np}{np(1-p)}$

$=\frac{1}{1-p}$

$=\frac{5}{4}$
$1-p=\frac{4}{5}$
$p=\frac{1}{5}$.
where $p$ being the probability of success.