Two numbers are selected at random from the first $40$ natural numbers. What is the probability that their sum is odd?

Three distinct numbers are selected from the first $100$ natural numbers. The probability that all three numbers are divisible by both $2$ and $3$ is:

$A$ box contains $10$ red marbles,$20$ blue marbles,and $30$ green marbles. If $5$ marbles are drawn from the box,what is the probability that at least one will be green?

$A$ bag contains $3$ white and $6$ red balls. Four balls are drawn at a time randomly. The probability of getting at least $2$ red balls is:

If the papers of $4$ students can be checked by any one of $7$ teachers,then the probability that all the $4$ papers are checked by exactly $2$ teachers is (in $/49$)

In a collection of $10$ tickets,there are $2$ winning tickets. From this collection,$5$ tickets are drawn at random. Let $p_1$ and $p_2$ be the probabilities of obtaining $1$ and $2$ winning tickets,respectively. Then $p_1+p_2$ lies in the interval: