Probability

• An Overview — the probability scale, the four rules and the common mistakes

The 9 National Curriculum subtopics

• P1 · Recording Outcomes: Tables and Frequency Trees — frequency tables, two-way tables and frequency trees
• P2 · Randomness, Fairness and Expected Outcomes — predicting how often an event should happen
• P3 · The Probability Scale and Relative Frequency — theoretical versus experimental probability
• P4 · Exhaustive and Mutually Exclusive Events — probabilities summing to one, and the complement rule
• P5 · Experimental Probability and Sample Size — why bigger samples are better, and detecting bias
• P6 · Listing Outcomes Systematically — the product rule, Venn diagrams and set notation
• P7 · Sample Space Diagrams — grids for two dice, spinners and combined experiments
• P8 · Combined Events and Tree Diagrams — independent and dependent events, with and without replacement
• P9 · Conditional Probability — two-way tables, Venn diagrams and reversing a conditional

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Each page contains step-by-step explanations, several worked examples and ten practice questions with fully worked solutions. All pages are self-contained HTML files that can be downloaded and used offline.