Q1 of 63 Page 976

If A and B are two events associated with a random experiment for which P(A) = 0.60, P(A or B) = 0.85 and P(A and B) = 0.42, find P(B).

Given : P(A) = 0.60, P(A or B) = 0.85 and P(A and B) = 0.42


To find : P(B)


Formula used : P(A or B) = P(A) + P(B) - P(A and B)


Substituting in the above formula we get,


0.85 = 0.60 + P(B) – 0.42


0.85 = 0.18 + P(B)


0.85 – 0.18 = P(B)


0.67 = P(B)


P(B) = 0.67


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