The Poisson distribution is one of the most commonly used distributions in statistics.
This calculator finds Poisson probabilities associated with a provided Poisson mean and a value for a random variable.
P(X = 3): 0.14037
P(X 3): 0.12465
P(X ≤ 3): 0.26503
P(X > 3): 0.73497
P(X ≥ 3): 0.87535