Fundamental Counting Principle

The fundamental counting principle is a method for determining the number of possible outcomes in a situation where there are multiple choices or stages.

The Principle

Example: Two-Stage Experiment

Example: Three-Stage Experiment

Permutations vs Combinations

Factorial Notation

Example: Factorial

Practice Problems

1. A restaurant offers 4 appetizers, 6 main courses, and 3 desserts. How many different meals can be formed?
2. Calculate and .
3. A lock has 4 dials, each with 6 letters. How many possible codes are there?
4. Explain when to use permutations vs combinations.