A permutation is an arrangement, or listing, of objects in which the order is important. In previous lessons, we looked at examples of the number of permutations of n things taken n at a time. Permutation is used when we are counting without replacement and the order matters. If the order does not matter then we can use combinations.
The following diagrams give the formulas for Permutation, Combination, and Permutation with Repeated Symbols. Scroll down the page with more examples and step by step solutions.
Permutations, Combinations
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