Given that the events A and B are such that P(A) = 1/2, P (A B) = 3/5 and P(B) = p. Find p if they are (i) mutually exclusive (ii) independent.


Given: P(A) =, P (A B) =and P(B) = p

(i) mutually exclusive


When A and B are mutually exclusive.


Then (A B) = ϕ


P (A B) = 0


As we know, P (A B) = P(A) + P(B) - P (A B)




(ii) independent


When A and B are independent.


P (A B) = P(A) . P(B)


P (A B) =


As we know, P (A B) = P(A) + P(B) - P (A B)





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