1. The problem is to understand and solve a question involving a tree diagram. 2. A tree diagram is a graphical representation used to list all possible outcomes of an event or series of events. 3. Each branch represents a possible outcome, and the probabilities along branches multiply to find the probability of combined events. 4. To solve a tree diagram problem, identify all branches and their probabilities. 5. Multiply probabilities along the branches to find the probability of each outcome. 6. Sum probabilities of desired outcomes if needed. 7. For example, if a tree has two branches with probabilities $p_1$ and $p_2$, the combined probability is $p_1 \times p_2$. 8. Always check that the sum of probabilities at each branching point equals 1. 9. This method helps in calculating complex probabilities step-by-step clearly and accurately. 10. If you provide a specific tree diagram question, I can help solve it with detailed steps.