What is the probability that the sum of two numbers chosen at random from $40$ consecutive natural numbers is odd?

In a consignment of $15$ articles,it is found that $3$ are defective. If a sample of $5$ articles is chosen at random from it,then the probability of having $2$ defective articles is

Find the probability that when a hand of $7$ cards is drawn from a well-shuffled deck of $52$ cards,it contains all $4$ Kings.

Out of $15$ players,there are $8$ batsmen and $7$ bowlers. What is the probability of selecting a team of $6$ batsmen and $5$ bowlers?

$A$ company representative is distributing $5$ identical samples of a product among $12$ houses in a row such that each house gets at most one sample. The probability that no two consecutive houses get one sample is

Let $A$ and $B$ be two finite sets having $m$ and $n$ elements respectively such that $m \le n.$ $A$ mapping is selected at random from the set of all mappings from $A$ to $B$. The probability that the mapping selected is an injection is