India and Pakistan play a $5$-test hockey series. What is the probability that India wins at least three games?

$A$ random variable $X \sim B(n, p)$. If the values of the mean and variance of $X$ are $18$ and $12$ respectively,then $n = $

If the sum of mean and variance of a Binomial Distribution is $\frac{15}{2}$ for $10$ trials,then the variance is (in $.5$)

$A$ coin is biased so that a head is twice as likely to occur as a tail. If the coin is tossed $3$ times,then the probability of getting two tails and one head is-

Let $X$ be a random variable having a Binomial distribution $B(7, p)$. If $P(X=3) = 5 P(X=4)$,then the variance of $X$ is:

If $X \sim B\left(8, \frac{1}{2}\right)$,then $P(|X-4| \leq 2)=$