Shmoop University
Shmoop: Basic Statistics & Probability: Factorials
The probability resource investigates factorials. Students learn about the topic through notes and examples. The tutorial consists of practice exercises to check for comprehension of the concept.
Mathigon
Mathigon: Combinatorics: World of Math
This lesson focuses on Combinatorics, a branch of mathematics which is about counting. It includes 5 sections: Factorials, Permutations, Combinations, Combinatorics and Pascal's Triangle, and Combinatorics and Probability with examples...
Wolfram Research
Wolfram Math World: Topics of Permutation
This MathWorld site is a lite to link to a multitude of sites involving permutations. Look through to find your specific needs. If you are looking at this site with regards to a probability and statisics class you will probably want to...
Other
Lake Tahoe Com. College: Fundamental Counting Principle
Explains the fundamental principle of counting, which is the beginning point for any study of counting techniques such as combinations and permutations.