The next part of the “counting” part of this unit is understanding the difference between two common patterns of counting: permutations and combinations. In brief, permutations are used to count the number of arrangements of objects, specifically when order matters like with ranked lists, unique assignments, or sequences. Combinations are used to count the number of groups of objects, specifically when order doesn’t matter like with committees or batches.
- Homework: HW 8.5 – Permutations and Combinations
- Notes: More details on the difference between these methods
- Lesson video 1: The difference between these methods (including also factorial)
- Lesson video 2: Calculating permutations and combinations (note that you can just use your calculator, instead of doing this by hand.