Combinations · nCr
Calculate combinations · ncr and see the working behind your result.
Inputs
Use the units shown—
Enter your values and select Calculate.
Formula & explanation
nCr = n!/[r!(n−r)!]
Variables & units
- Number of objects · n
- Numeric value · minimum 0, maximum 50
- Number to choose · r
- Numeric value · minimum 0, maximum 50
Worked example
Choosing 3 objects from 10 gives 120 combinations.
Assumptions
Inputs are integers from 0 to 50. Exact integer arithmetic is used before conversion to a safe numeric result.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
Use the default input values to find the answer. The reset icon restores those values.
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