If $A$ And $B$ Are Mutually Exclusive Events With $P(A)=0.15, P(B)=0.45$ , Then $P\left\{(A \cup B)^{\prime}\right\}$

Short Answer

If $A$ and $B$ are mutually exclusive events with $P(A)=0.15, P(B)=0.45$ , then $P\left\{(A \cup B)^{\prime}\right\}$ equals _______.