Question 310570
P(A)= 0.31
P(B | A)= 0.8
P(A and B)= ?
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p(B | A) = P(A and B)/P(A)
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So, P(A and B) = P(B | A)*P(A)
= 0.8*0.31 
= 0.248
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cheers,
stan H.