I have 2 events, $A$ and $B$ which are in a space $S$, such that $P(A')=0.3$, $P(B)=0.5$ and $P(A' \bigcup B')=0.7$.
I need to answer a series of questions based upon this information, but I'm running into a brick wall almost immediately.
Let's say I need to find $P(A \bigcup B)$. As far as I can tell, the formula for this depends on whether it's independent or dependent.
However it's not until the final question that I'm asked whether A and B are independent. Do I not need to know this before I answer any of the previous questions? Where do I even begin here?