If $A$ and $B$ are mutually exclusive events with $P(A)=\frac{1}{4}$ and $P(B)=\frac{3}{7}$,then what is the value of $P(A / A \cup B)$?

An integer $x$ is chosen at random from $1$ to $50$. The probability that $x + \frac{336}{x} \leq 50$ is

One card is drawn from a well-shuffled deck of $52$ cards. If each outcome is equally likely,calculate the probability that the card will not be a black card.

Each of the two boxes $A$ and $B$ contain $10$ chits numbered $1$ to $10$. If one chit is drawn at random from each of $A$ and $B$,then the probability that the number on the chit drawn from $A$ is smaller than the number on the chit drawn from $B$,is

$A$ non-zero integer $x$ is selected randomly from the set of integers $\{x \in Z \mid -25 \leq x \leq 25, x \neq 0\}$. The probability that $x + 6 \leq \frac{135}{x}$ is

The probability of getting a total of $5$ or $6$ in a single throw of $2$ dice is