Math & Statistics
Combinations (nCr) Calculator
Calculate the number of unordered combinations of r items from n.
Your inputs
Change any value to update the result instantly.
nCr
210
n!
36,28,800
r!
24
(n-r)!
720
Formula and working
nCr = n! ÷ (r!(n−r)!)
- 1
Substitute your values
n (total items) = 10; r (items chosen) = 4
- 2
Apply the formula
nCr = n! ÷ (r!(n−r)!) = 210
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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