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Combination Calculator (n choose k)

Compute the number of ways to choose k items from n without order.

Input Data

N
K

Results

Number of combinations.
120
Explanatory note about the result.
C(10,3)=C(10,7)

At a glance:C(n,k) = n!/(k!(n−k)!), counting unordered selections. Complements combinations and permutation.

Formula

C(n,k) = n! / (k!(n−k)!).

How to Use

  1. Enter n and k.
  2. The tool returns the count.

Case Studies

n=5, k=2

C(5,2) = 10.

FAQ

Combination vs permutation?

Combination ignores order; permutation counts ordered arrangements.

Related Tools

References

Content review: Calculatorism Science Team. Results are for reference only; please refer to the relevant authorities for the official figures.

Found a problem with the results?

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