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Ledger · Statistics

Probability Calculator

Three classic scenarios, one page. Flip a coin N times and ask the odds of exactly K heads. Roll dice and ask about sums. Count how many ways K items can be chosen from N.

Binomial — N trials, K successes

P(X = 5)
24.6094%
P(X ≤ 5)
62.3047%
P(X ≥ 5)
62.3047%

P(X=k) = C(n,k) · pk · (1−p)n−k