Answer:
P(B) = 0.20
Step-by-step explanation:
For these events, which are not independent or mutually exclusive, the relation between the various probabilities is ...
P(A or B) = P(A) +P(B) -P(A and B)
Solving for P(B), we find ...
P(B) = P(A or B) +P(A and B) -P(A)
P(B) = 0.77 +0.13 -0.7 = 0.20
The probability of B is 0.20.
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Additional comment
The formula applies to independent and mutually exclusive events, as well. For independent events, P(A and B) = P(A)·P(B). For mutually exclusive events, P(A and B) = 0.
