Complement rule
Definition · Level 11 · Interview practice
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For “at least one” questions, compute 1 − P(none) instead of adding overlapping probabilities.
Example
At least one six in four rolls = 1 − (5/6)4 ≈ 51.8%.
Where Tradecraft teaches it
Level 11 · Interview practice, in the lesson “Probability & expected value classics”: The puzzles interviewers often recycle, and the five tools that crack them.
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