• ### Unit 6: Introduction to Counting and Probability

Counting is not always as easy as it sounds. Say, for example, you are asked to arrange three balls of three different colors. What are the possibilities? What if two of them have the same color? This is an example of a set of problems known as "counting problems.” In this unit, we will learn different types of counting using possibility trees and general counting theorems. Once we understand the concepts of counting, we will discuss the probability of event occurrence, which refers to the likelihood that a certain outcome for a given problem set will occur. Events can be dependent or independent, making them subject to different sets of rules. Throughout the unit, we will relate counting and probability to computer science topics such as counting list and array elements, password computation, and brute force attacks.

In this unit, we are going to rely on the Devadas and Lehman reference as primary. Use the Bender and Williamson reference as a supplement.

Completing this unit should take you approximately 15 hours.