**Unit Overview:**In this unit, students will recall general knowledge about conditional probability and compound events learned in 7th grades. They will further learn to use addition rule, multiplication rule, permutation and combinations to compute probability and evaluate outcomes. All the knowledge learned in this unit will lead them to use probability to evaluate outcomes of more complex situations in their next course.

**Enduring Understanding:**- Probability is a ratio of the number of outcomes in an event to the number of possible outcomes, known as a sample space.

- Compound events include mutually exclusive events, independent events, and dependent events.
- Probabilities are used to make fair decisions in the real world.

**Essential Questions:**- How can you describe two events and interpret their relationship through probability concepts?
- What are the differences and similarities between computation methods of compound events?
- How can you use probability to analyze decisions based on its concepts?