A Poisson variable X has mean 2. Using e⁻² = 0.1353, P(X ≥ 1) is:

Correct answer: D) 0.8647

Explanation

P(X = 0) = e⁻ᵐ m⁰/0! = e⁻² = 0.1353. P(X ≥ 1) = 1 − P(X = 0) = 1 − 0.1353 = 0.8647. 0.2707 is P(X = 1) = 2e⁻².