Mathématiques · Glossaire
What is Permutation?
Définition rapide
An arrangement of items in a specific order. Number of ways to arrange n items = n! (n factorial).
Explication complète
A permutation is an ordered arrangement of items. The number of permutations of n distinct items is n! (n factorial = n×(n-1)×(n-1)...×1). For example, 3! = 6 ways to arrange 3 items. Permutations of n items taken k at a time is n! / (n-k)!. Permutations are used in probability, cryptography, scheduling, and rank calculations. They differ from combinations: in a permutation, ORDER matters (AB ≠ BA); in a combination, order does not. "How many ways to arrange 5 people in a line" = 5! = 120. "How many 3-person committees from 10 people" = 10C3 = 120 — a combination.
Calculatrices liées
Calculators that use or explain Permutation.
Termes liés
More from Mathématiques
Standard Deviation
A measure of how spread out numbers are from their mean. Low = consistent, high = volatile.
P-Value
The probability of observing results at least as extreme as those observed, assuming the null hypothesis is true.
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The sum of values divided by the count. The most common type of "average." Sensitive to outliers.
Median
The middle value in a sorted list. Half the values are above, half below. Robust to outliers.
Pythagorean Theorem
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Logarithm
The exponent to which a base must be raised to produce a given number. log(100) = 2 means 10² = 100.
Last reviewed: June 15, 2026 • Category: Mathématiques