Question 1024418
A fair coin is tossed 4 times. Find the conditional probability that the results are all heads given that they are not all tailes. 
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P(4heads | not 4 tailes) = P(4heads and not 4 tailes)/P(not 4 tailes)
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= (1/16)/(15/16) = 1/15
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Cheers,
Stan H.
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