A-level · Probability
Permutations and combinationsExam-style questions
Counting arrangements and selections — factorials, arrangements with repeated items, ordered selections (nPr), unordered selections (nCr), and the standard restriction tricks: objects kept together, objects separated, and "at least" counts built case by case or by complement.
0 questions · A-level level · mark scheme and worked solution on each · no sign-up to try
No questions on this concept at this level yet. Read the lesson or browse the rest of Probability.