In this module, we explore various aspects of probability with topics ranging from definitions and formulae to possibility diagrams. We will cover the probability of an event not occurring as well as independent and mutually exclusive events. With the help of practice questions and an example, the concepts of relative frequency, bias, unitary method, and finding the number of people based on probability are all included. Finally, there are instructions for constructing possibility diagrams and determining which set a result belongs to when multiple sets are present. • Define and calculate probability, relative frequency, and experimental probability • Learn how to calculate the probability of an event not occurring and find bias • Understand unitary method and how to calculate the probability of finding the number of people • Construct possibility diagrams and calculate probability from them • Determine which set a result belongs to if multiple sets are present • Understand independent and mutually exclusive events and use their formulae to calculate probability