In this lesson you learned how to find the number of permutations of objects in several ways. These ways included making a list, drawing a tree diagram, drawing blanks, using the fundamental counting principle, and using the permutation formula, nPr. You learned that there are fewer permutations if there are identical items and that some methods of determining the number of permutations are better and more efficient than others depending upon the question posed.
In Lesson 3 you will learn about the number of choices of elements when order does not matter.