If a random variable $X$ follows the Poisson distribution with variance $3$,then $P(X=r)$ is maximum,when $r=$

$A$ random variable $X$ has the following probability distribution:

$X = x$	$0$	$1$	$2$
$P(X = x)$	$4k - 10k^2$	$5k - 1$	$3k^3$

Then $P(X < 2)$ is:

If the probability function of a random variable $X$ is given by $P(X=j) = \frac{1}{2^j}$ for $j = 1, 2, 3, \ldots, \infty$,then the variance of $X$ is:

$A$ random variable $X$ has the following probability distribution:

$X=x_i$	$-2$	$-1$	$0$	$1$	$2$
$P(X=x_i)$	$1/6$	$k$	$1/4$	$k$	$1/6$

The variance of this random variable is

In a game of throwing $3$ coins,a player loses $₹ 5$ for each head and gains $₹ 10$ for each tail. If a random variable $X: S \rightarrow R$ is defined as $X(a) = \text{net gain } (a \in S)$,then the mean of the random variable is (in rupees):

$A$ random variable $X$ takes the values $0, 1, 2$. Its mean is $1.2$. If $P(X=0)=0.3$,then $P(X=1)=$