What is the combinations formula?

C(n,r) = n! / (r! × (n-r)!). Order does not matter.

What is the difference between combinations and permutations?

Combinations: order doesn't matter (AB = BA). Permutations: order matters.

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Calculate C(n,r) — the number of ways to choose r items from n without order. Uses n!/(r!(n-r)!).

n (total items)

r (choose)

What is the combinations formula?: C(n,r) = n! / (r! × (n-r)!). Order does not matter.
What is the difference between combinations and permutations?: Combinations: order doesn't matter (AB = BA). Permutations: order matters.
Is this tool free?: Yes. All tools on QuickFreeTools are free with no signup.

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