I cannot seem to get one portion of this problem right.

Question

An experiment consists of two independent trials. The outcomes of the first trial are A, B, and C, with probabilities of occurring equal to 0.2, 0.6, and 0.2, respectively. The outcomes of the second trial are E and F, with probabilities of occurring equal to 0.4 and 0.6. Draw a tree diagram representing this experiment. Use this tree diagram to find the probabilities below. What is P(F|B)? (there was more to the problem, but I finished the rest)

Answer 1

The notation P(F|B) means what is the probability of F, given that B has occurred.

 

Let you finger do the tracing!  B has occurred, so go to the end of that branch of the tree's first stage.

 

With that as a new starting position now (B has occurred), the probability of F  happening is 0.6

 

Answer: 0.6