What is the probability of getting a sum $9$ from two throws of a dice?

$2$ dice are thrown. Find the probability of getting a sum less than $6$.

$A$ bag contains $4$ white,$5$ red,and $6$ black balls. If two balls are drawn at random,then the probability that one of them is white is

If $A$ and $B$ are two independent events such that $P(A) = \frac{1}{2}$ and $P(B) = \frac{1}{5}$,then which of the following is true?

Tickets numbered $1$ to $20$ are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of $3$ or $5$?

$A$ bag $x$ contains $3$ white balls and $2$ black balls and another bag $y$ contains $2$ white balls and $4$ black balls. $A$ bag and a ball out of it are picked at random. The probability that the ball is white,is