The problem is:
A certain shop repairs both audio and video components. Let A denote the event that the next component brought in for repair is an audio component, and let Bbe the event that the next component is a compact disc player (so the event B is contained in A). Suppose that $P(A)=.6$ and $P(B)=.05$ What is ? $P(B|A)$
If I knew $P(A \cap B)$, then I could calculate $P(A \cup B)$. I thought by introducing a new set, one that is the complement of $A$, I could someone how make this problem work. I introduced the set $V$, which is the event someone brings in an video component, and then $P(A) + P(V) = 1 \implies P(V) = .4$. However, this didn't seem--ostensibly at least--to provide any help. Could someone prod me along?