$A$ card is drawn at random from a pack of $52$ cards. The probability of this card being a red card or a queen is:

If the odds against an event be $2 : 3$,then the probability of its occurrence is

Two dice are thrown simultaneously. The probability that the sum is odd or less than $7$ or both is:

$A$ person $P$ speaks the truth in $75\%$ of cases and another person $R$ in $80\%$ of cases. What is the probability that they are likely to contradict each other in narrating the same event?

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

$A$,$B$,and $C$ are three events,one of which must and only one can happen. The odds in favor of $A$ are $4 : 6$,and the odds against $B$ are $7 : 3$. Thus,the odds against $C$ are: