The probability of drawing a white ball from a bag containing $3$ black balls and $4$ white balls is:

When $2$ dice are thrown,find the probability of getting a sum that is a prime number.

From a class of $12$ girls and $18$ boys,two students are chosen randomly. What is the probability that both of them are girls?

Let $0 < P(A) < 1$,$0 < P(B) < 1$ and $P(A \cup B) = P(A) + P(B) - P(A)P(B).$ Then

$A$ bag contains $6$ white,$7$ red,and $5$ black balls. If $3$ balls are drawn from the bag at random,then the probability that all of them are white is

$A$ basket contains $5$ apples and $7$ oranges,and another basket contains $4$ apples and $8$ oranges. One fruit is picked out from each basket. Find the probability that the fruits are both apples or both oranges.