Question

If P(A or B) = 0.8, P(A) = 0.3, and P(A and B)= 0.15, find P(B).
P(B) =
(Simplify your answer. Type an integer or a decimal.)

Answer 1

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Answer:

  P(B) = 0.65

Step-by-step explanation:

The appropriate formula is ...

  P(A or B) = P(A) +P(B) -P(A and B)

Then P(B) is ...

  P(B) = P(A or B) +P(A and B) -P(A)

  P(B) = 0.8 +0.15 -0.3

  P(B) = 0.65