In a simultaneous toss of $2$ coins,find the probability of getting $2$ tails.

$A$ bag contains $3$ red and $5$ black balls and a second bag contains $6$ red and $4$ black balls. $A$ ball is drawn from each bag. The probability that one is red and the other is black,is

An urn contains $25$ balls numbered $1$ to $25$. Suppose an odd number is considered a 'success'. $2$ balls are drawn from the urn with replacement. Find the probability of getting exactly $2$ successes.

The event $A$ is independent of itself if and only if $P(A) = $

$A$ box contains $4$ white pens and $2$ black pens. Another box contains $3$ white pens and $5$ black pens. If one pen is selected from each box,then the probability that both the pens are white is equal to

Three cards are drawn at random from a pack of $52$ cards. What is the chance of drawing three aces?