Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 4F Solution Created 2026-09-24 Updated 2026-10-14
Pairwise independent events satisfy for every distinct pair. Independent events satisfyfor every nonempty subset of the indices. For three events this includes the triple intersection, not just the three pairwise intersections.
Write . Disjointness gives , while every intersection of two or three distinct is exactly . Thus pairwise independence is equivalent to . Since ,For , this is an admissible nonnegative : putting gives . The four disjoint events can therefore have the stated probabilities, with the remaining probability assigned to their complement. This also covers .
Full independence would additionally require . Together with , this forces to be zero or one. The first case gives ; the second gives . Neither allows positive . There are no such mutually independent events with and .
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 3F c Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 3F b Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 3F a Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 2A b Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 2A a Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 1A b Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 1A a Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 12F b Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 12F a Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 11F e Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 11F d Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 11F c Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 11F b Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 11F a Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 10F b Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 2 10F a Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 1 9F c Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 1 9F b Created 2026-09-24 Updated 2026-09-24
Past exam of the mathematics course of the University of Cambridge 2011 ia Paper 1 9F a Created 2026-09-24 Updated 2026-09-24
There are unlisted articles, also show them or only show them.