TATITIC CALCULATOR
Permutation
A precise tool.
What is the Permutation & How does it work?
A permutation counts the number of ways to arrange r distinct objects selected from a set of n distinct objects where order matters.
The formula derives from the fundamental principle of counting: for the first position you have n choices, for the second n‑1, and so on until r positions are filled.
Because the product n·(n‑1)…(n‑r+1) equals n!/(n‑r)!, the compact notation P(n,r) is commonly used in combinatorics and probability.
P(n,r)=\frac{n!}{(n-r)!}
P = number of permutations
Parameters
Result
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Frequently Asked Questions
What is a permutation?
A permutation is an arrangement of objects in a specific order. For example, arranging 3 books out of 5 can be done in P(5,3) ways.
How do I calculate permutations using this calculator?
Enter the total number of objects (n) and the number of objects to arrange (r). The calculator will compute the number of permutations using the formula P(n,r) = n! / (n-r)!.
Can I use this calculator for combinations?
No, this calculator is specifically for permutations where order matters. For combinations, you would need a different type of calculator.
What does the exclamation mark (!) mean in the formula?
The exclamation mark denotes a factorial, which means multiplying all positive integers up to that number. For example, 5! = 5 × 4 × 3 × 2 × 1.
When would I use permutations in real life?
Permutations are used in various fields such as computer science for arranging data, cryptography for creating secure codes, and even in sports for scheduling matches.
Results are for informational purposes only and do not constitute professional advice.