Q59 of 249 Page 31

Mark the correct alternative in each of the following:

Let A and B be two events such that P(A) = 0.6, P(B) = 0.2 and P(A/B) = 0.5. Then equals.


P(A) = 0.6 , P(B) = 0.2 , P = 0.5 → (Given)



→ (1)



= 1 – 0.2


= 0.8


Also,



= 1 – P(A⋃B) → (3)


Using (2) & (3) in Equation (1) we get,


→ (3)


Now,



P(A∩B) = 0.5 P(B) → From (Given)


P(A∩B) = 0.5 0.2


P(A∩B) = 0.1


According to the addition theorem of probability,


P(A⋃B) = P(A) + P(B) – P(A⋂B)


= 0.6 + 0.2 – 0.1


= 0.8 – 0.1


= 0.7 → (4)


Putting (4) in equation (3) we get,




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