CCalcBOX
🌐JA
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Probability & Combinations

Calculate permutations, combinations, binomial and normal distributions.

nPr (10P3)
720
nCr (10C3)
120

nPr = n! / (n-r)! = 10! / 7!

nCr = n! / ((n-r)! × r!) = 10! / (7! × 3!)

📖How to Use
  1. 1Select the probability calculation type (combinations, permutations, binomial distribution, etc.)
  2. 2Enter the required parameters
  3. 3See the probability value and calculation steps
💡Tips & Knowledge
  • Combinations: C(n,r) = n! ÷ (r! × (n−r)!); Permutations: P(n,r) = n! ÷ (n−r)!
  • The probability of getting 6 or more heads in 10 coin flips follows a binomial distribution
  • Birthday paradox: with just 23 people, there's over a 50% chance two share a birthday

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