# Permutations Formula

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**Formula:** `P(n, r) = n! / (n - r)!`

The Permutations Formula calculates the number of ways *r* items can be selected from *n* items without replacement, where order matters. Mathematically, it's expressed as **P(n, r) = n! / (n - r)!**, where *!* denotes factorial, which is the product of all positive integers up to that number. In practical applications, permutations are used in situations where the arrangement of items is crucial, such as seating arrangements, race outcomes, or any scenario where the order affects the result.

Tags: Algebra, Permutations, Combinations, Factorial