Probability Multiplication law for dependent events GCSE Statistics Probability Multiplication law for dependent events
Two events are not independent if the outcome of one event effects the outcome of the second. For example the weather in the UK can effect the attendance at a football match or summer fair. The prospect of cold or rain can put people off attending. The probability of drawing a coloured ball from a bag is effected if the ball is not replaced. If A and B are not independent events then: P(A and B) = P(A ∩ B) = P(B|A) x P(A) = P(A|B) X P(B) P(B|A) this means the probability of B given that A happens (the line thing is read as given that) the questions in the book can all be solved using tree diagrams !
Your turn exercise 7K page 283