If $A$ and $B$ are two events such that $P(A) = 0.4$,$P(A \cup B) = 0.7$ and $P(A \cap B) = 0.2$,then $P(B) = $

The odds against a certain event are $5: 2$ and the odds in favour of another independent event are $6: 5$. The probability that at least one of the events will happen,is

Let $A$ and $B$ be two independent events of an experiment. If $P(A) = 0.3$ and $P(A \cup B) = 0.8$,then find $P(A \to B)$,where $P(X)$ denotes the probability that statement $X$ is true.

In an entrance test that is graded on the basis of two examinations,the probability of a randomly chosen student passing the first examination is $0.8$ and the probability of passing the second examination is $0.7$. The probability of passing at least one of them is $0.95$. What is the probability of passing both?

For two events $A$ and $B$,if $P(A \cup B) = 5/6$,$P(A^c) = 5/6$,and $P(B) = 2/3$,then $A$ and $B$ are

For two events $A$ and $B$,$P(A)=0.5$,$P(A \cup B)=0.6$ and $P(B)=K$ are given. If $A$ and $B$ are independent events,then $K=$ . . . . . . .