<PRE><B>Question 465190</B>
Joe feels the probability of getting an A in history is .3, 
the probability of getting an A in psychology is 0.4, 
and the probability of getting an A in history or Psychology is 0.6 .
 What is the probability of getting an A IN BOTH SUBJECTS?
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P(a and b) = P(a) + P(b) - P(a or b)
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P(hist and psyc) = 0.3 + 0.4- 0.6 = 0.1
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Cheers,
Stan H.
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