This is probably a simple question but I can't get it P(A)=0.5 and P(AuB)=0.6, find P(B) if A and B are independent
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Originally Posted by Happy Dancer This is probably a simple question but I can't get it P(A)=0.5 and P(AuB)=0.6, find P(B) if A and B are independent A and B are independent so $\displaystyle P(A \cup B)=P(A)+P(B)-P(A)B(B)$. Now solve for $\displaystyle P(B)$.
Thanks, btw I have another problem. Find P(B) given that P(A|B)=0.4 P(B)=P(AnB)/P(A|B)=P(A)P(B)/P(A|B) so P(B)=1.25 P(B) How can this be right?
Originally Posted by Happy Dancer Thanks, btw I have another problem. Find P(B) given that P(A|B)=0.4 P(B)=P(AnB)/P(A|B)=P(A)P(B)/P(A|B) so P(B)=1.25 P(B) How can this be right? What you have done is not correct! You must have been given some information about $\displaystyle P(A)$.
Yes, carrying on from the previous question P(A)=0.5
Originally Posted by Happy Dancer Yes, carrying on from the previous question P(A)=0.5 If A & B are independent then $\displaystyle P(A)=0.4 \ne 0.5$! So there is a mistake in the problem. Why not post the exact question.
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