By entering terms for how you want to combine items, you can use this calculator to determine all the different combinations and permutations you can have. For more advanced users, various rules are explained and how to use them.

Combinations and permutations are explained clearly, with lots of examples. Includes practice questions.

Use this tutorial to understand factorials.

Probability questions using permutations and combinations of objects. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

[Free Registration/Login may be required to access all resource tools.] Here you'll learn about theoretical and experimental probability, including how to describe sample spaces and how to conduct probability simulations. Includes...

Reference material and practice problems for the binomail theorem.

This CoolMath resource will help students understand the concept of permutations when the combination has something repeated.