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Let $P(E)$ denote the probability of the occurrence of event $E$. If $P(A)= 0.5$ and $P(B)=1$ then the values of $P(A|B)$ and $P(B|A)$ respectively are

  1. $0.5, 0.25$
  2. $0.25, 0.5$
  3. $0.5, 1$
  4. $1, 0.5$
asked in Probability by Veteran (29k points)   | 419 views

1 Answer

+5 votes
Best answer

P(A)= 0.5

P(B)=1

Here there is no dependency in event A and B. 
So  P(A $\cap$ B) = P(A) * P(B)

P(A/B)= probability of occurrence  of event A when B has already occurred

            = P(A $\cap$ B) / P(B) 

            = (0.5 * 1) /1 = 0.5

 

P(B/A)= probability of occurrence  of event B when A  has already occurred 

            = P(B $\cap$ A) / P(A) 

            = (1 * 0.5) / 0.5 =  1

Ans- C

         

answered by Veteran (24.3k points)  
edited by
HOW U KNOW THERE IS NO DEPENDENCY
@ashutosh , Since there is nothing said about dependency so I assumed both A and B are  independent event.
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