In a single throw of two dice,the probability of obtaining a total of $7$ or $9$ is:

Five horses are in a race. $Mr. A$ selects two of the horses at random and bets on them. The probability that $Mr. A$ selected the winning horse is (in $/5$)

$5$ boys and $5$ girls are sitting in a row randomly. The probability that boys and girls sit alternatively is

Two dice are thrown together. If the numbers appearing on the two dice are different,then what is the probability that the sum is $6$?

Fifteen persons,including $A$ and $B$,sit down at random at a round table. The probability that there are $4$ persons between $A$ and $B$ is

If $A$ and $B$ are two events such that $P(A) = \frac{3}{8}$,$P(B) = \frac{5}{8}$ and $P(A \cup B) = \frac{3}{4}$,then $P(A|B) = $