Answer: 9e⁻³/2.
- A 3e⁻³/2
- B 9e⁻³/2
- C e⁻³
- D 3e⁻³
Correct answer: B. 9e⁻³/2
Explanation: Poisson PMF: P(X=k) = e<sup>−λ</sup>·λᵏ/k!. With λ=3, k=2: P(X=2) = e<sup>−3</sup>·3²/2! = e<sup>−3</sup>·9/2 = 9e<sup>−3</sup>/2 ≈ 0.224. Verify: 9×0.0498/2 ≈ 0.224.
Venn diagram of the universal set U with events A and B, showing the intersection (A and B), the parts unique to each event, and the complement region outside both.
Concept context
Chance, events, conditional probability, and Bayes theorem