In a lottery $50$ tickets are sold in which $14$ are prize-winning tickets. $A$ man bought $2$ tickets,then the probability that the man wins at least one prize is:

$A$ husband and wife appear in an interview for $2$ vacancies in the same post. The probability of husband's selection is $\frac{1}{7}$ and that of wife's is $\frac{1}{5}$. What is the probability that none of them will be selected?

$A$ jar contains $3$ red marbles,$7$ green marbles and $10$ white marbles. If a marble is drawn from the jar at random,what is the probability that this marble is white?

$A$ bag $X$ contains $2$ white and $3$ black balls and another bag $Y$ contains $4$ white and $2$ black balls. One bag is selected at random and a ball is drawn from it. Then the probability for the ball chosen to be white is

If out of $20$ consecutive whole numbers two are chosen at random,then the probability that their sum is odd,is

$A$ pack of cards contains $4$ aces,$4$ kings,$4$ queens,and $4$ jacks. Two cards are drawn at random. The probability that at least one of these is an ace is: