$A$ bag contains $6$ red,$5$ white and $4$ black balls. Two balls are drawn. The probability that none of them is red,is

You are given the digits $2, 3, 4, 6,$ and $7$. In how many ways can you form a $3$-digit number without repetition of digits that is odd and greater than $300$?

When two dice are rolled,what is the probability that the sum of the numbers appearing is $\leq 10$?

$A$ Chartered Accountant applies for a job in $2$ firms $X$ and $Y$. The probability of his being selected in firm $X$ is $0.7$,and being rejected at $Y$ is $0.5$,and the probability of at least $1$ of his applications being rejected is $0.6$. What is the probability that he will be selected in $1$ of the firms?

From a pack of cards,two are drawn,the first being replaced before the second is drawn. Find the probability that the first is a diamond and the second is a king.

There are two children in a family. The probability that both of them are boys is