If there are $n$ independent trials,$p$ and $q$ are the probability of success and failure respectively,then what is the probability of exactly $r$ successes?

$A$ die is thrown $5$ times. Getting an odd number is considered a success. Find the variance of the distribution of successes.

In an experiment, a person gets success $\alpha$ times out of $\beta$ trials. If the experiment consists of $n$ trials, then the probability that he fails at least $(n-1)$ times is

$A$ random variable $X \sim B(n, p)$ follows a binomial distribution with $n = 6$. If $9P(X = 4) = P(X = 2)$, then the probability of success $p$ is:

For a Binomial distribution,$n=6$,if $9 P(X=4)=P(X=2)$,then $q=$

An ordinary dice is rolled for a certain number of times. If the probability of getting an odd number $2$ times is equal to the probability of getting an even number $3$ times,then the probability of getting an odd number for an odd number of times is