Probability is the ratio of favorable outcomes to total outcomes. It explains the chances of an event occurring. Whenever you weigh the odds of whether or not to do your homework or study for an exam, you are using probability. Politicians study polls to hypothesize their likelihood of winning an election. Teachers choose a particular course of study based on what they think students will understand. Doctors choose the treatments needed for various diseases based on their assessment of likely results.

In this unit, you will learn to solve probability problems using a systematic approach. By the end of this unit, you will be able to understand and use the terminology of probability including combinations, permutations, and counting principles and use them to determine the number of possible outcomes. You will also be able to determine whether two events are mutually exclusive and whether two events are independent.