Oswego City School District
Regents Exam Prep Center: Factorials
This math tutorial defines factorial notation and features practice problems and a teacher resource page.
Wolfram Research
Wolfram Math World: Factorial
This page gives a very complete description of the use of factorials in mathematics. The most general information is at the top.
Khan Academy
Khan Academy: Calculating Factorials (Practice)
This is a 7-problem quiz/practice on calculating factorials.
Varsity Tutors
Varsity Tutors: Hotmath: Algebra Review: Factorials
Find a quick, concise explanation of factorials. An example is given and clearly explained.
Texas Instruments
Texas Instruments: Counting Principle, Combinations, and Permutations
Students will solve discrete math problems involving permutations, factorials, and combinations. Students are responsible for deciding which is appropriate to solve a given word problem.
Interactive Mathematics
Interactive Mathematics: Counting and Probability
An introduction to the concept of counting and probability includes working with factorials and finding the probability of an event.
CK-12 Foundation
Ck 12: Probability: Combination Problems Grade 8
[Free Registration/Login may be required to access all resource tools.] Use combination notation to evaluate combinations.
CK-12 Foundation
Ck 12: Probability: Permutation Problems Grade 8
[Free Registration/Login may be required to access all resource tools.] Use permutation notation to evaluate a permutation
CK-12 Foundation
Ck 12: Probability: Permutations and Combinations Compared
[Free Registration/Login may be required to access all resource tools.] Covers the formula for permutations.
CK-12 Foundation
Ck 12: Permutations and Combinations Compared Grades 9 10
[Free Registration/Login may be required to access all resource tools.] Given a set, learn how to calculate its number of permutations.
CK-12 Foundation
Ck 12: Probability: Permutations Grades 9 10
[Free Registration/Login may be required to access all resource tools.] Given a set, learn how to calculate its number of permutations.
Math Notes and Math Tests
Pre Calculus Notes: Sequences and Series [Pdf]
The tutorial discusses sequences and series. Students learn about factorials, recursively defined sequences, and summation notation. The resource consists of class notes and examples with solutions.
CK-12 Foundation
Ck 12: Probability: Permutation Problems Grades 9 10
[Free Registration/Login may be required to access all resource tools.] Count and evaluate permutations.
CK-12 Foundation
Ck 12: Probability: Permutation Problems Grade 7
[Free Registration/Login may be required to access all resource tools.] Count and evaluate permutations.