Suppose that R and S are events in a certain probability space such that $P[R∣S]=0.52$, $P[S∣R]=0.65$ and $P[R\cap S]=0.26$.
I have found that $P[R]=0.4$ and $P[S]=0.5$.
I thought this was asking for $P[R \cup S]$ so I calculated $P[R]+P[S]-P[R\cap S]=0.4+0.5-0.26 = .64$, but this answer isn't write. I think I may be misinterpreting the question. Any help would be appreciated.