Conditional Probability & Multiplication Rules

Learn conditional probability through restricted populations, sampling without replacement and multistage project trees. Work from direct ratios to full-history chain rules, missing branches, feasibility checks and subtle null-event distinctions. Prerequisites: event operations, probability axioms and counting. Tree branches are stated in text so every problem is self-contained. Includes single-select and multiselect questions with worked solutions and distractor feedback.

References: 1.4.0 Definition, conditional axioms and chain rule.