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# conditional probability help!!! watch

1. hey guys, please can somebody help me with this question.

3. During a court case the jury has to decide whether or not an unlikely event has occurred based
upon the testimony of two independent witnesses. Let:-
• ¿ be the probability of the unlikely event occurring;
• ® be the probability witness A tells the truth;
• ¯ be the probability witness B tells the truth.
Given that both witnesses claim that the event occurred:-
(a) What is the probability that the event occurred? [3]
(b) Given that ¿ = 0.001, ® = 0.95 and ¯ = 0.8, what is the probability that the event occurred?
[2]
(c) Given that ¿ = 0.001 and ¯ = ®, what value of ® gives probability 0.5 of the event having
occurred? [3]
2. comon mna sort this question out

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Updated: November 10, 2008
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