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🔢 Permutations & Combinations

🔢 Permutations & Combinations

Calculate permutations (nPr) and combinations (nCr) — how many ways to arrange or select items.

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📐 Formulas
  • Permutation (nPr): n! / (n-r)! — order matters
  • Combination (nCr): n! / (r!(n-r)!) — order doesn't matter
  • Example: 5 items, choose 3 → nPr=60, nCr=10

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