Combination Sum Calculator
Calculate the number of combinations possible for given set sizes.
About
The combination sum calculator allows you to determine the number of ways to choose a subset of items from a larger set. This is useful in fields like statistics, probability, and combinatorics where you need to calculate possible selections.
The formula to calculate combinations is:
C(n, r) = n! / (r! * (n-r)!)
Quick Reference
| n | r | C(n, r) |
|---|---|---|
| 5 | 2 | 10 |
| 6 | 3 | 20 |
| 10 | 4 | 210 |
| 8 | 2 | 28 |
| 7 | 5 | 21 |
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