Answer: Number of trials until first success.
- A Number of successes in n trials
- B Number of trials until first success
- C Rare events
- D Continuous outcomes
Correct answer: B. Number of trials until first success
Explanation: Geometric distribution: X = number of trials needed to get first success. P(X=k) = (1-p)<sup>k-1</sup> × p.
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