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If my team wins 50% of the time when I wear my lucky tie and 90% when I wear my yellow sox, what is the probability of them winning if I wear both. explain how you got to your response, please

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What are your ideas? Can you show your work so far? – Ataraxia May 14 '13 at 17:45
The probability we lose wearing lucky tie is $0.5$, and the probability we lose wearing yellow socks is $0.10$. On the completely unjustifiable assumption of independence, the probability we lose if we wear both is $(0.5)(0.10)$. But maybe it is far higher than that. The gambling syndicate that has been stringing you along may get offended at being manipulated so crudely. – André Nicolas May 14 '13 at 18:03
+1 good question but you haven't seen your effort – iostream007 May 14 '13 at 18:14
Well the question is the information that you should supply. Are these two events dependent or independent? – Sina May 14 '13 at 18:36

The probability of them winning remains the same, since an individual's choice of clothes does not influence the results of sporting events (unless you're bribing the players).

On a more serious note, you can't calculate this without some more information, since: $$P(C \ |\ A \cap B) $$ Is not necessarily related to $P(C\ | \ A)$ and $P(C\ | \ B)$, which is the information you provided.

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