Question 1073632
P(A) = 7/20, P(A u B) = 191/400, P(A n B) = 49/400, P(B)=? 
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P(A u B) = P(A)+P(B) - P(A n B)
191/400 = 7/20 + P(B) - 49/400
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191 = 7*20 + P(B) - 49
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P(B) = 191-140+49
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P(B) = 100
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Cheers,
Stan H.
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