- #1

daewoo

- 25

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## Homework Statement

Suppose that P(A) = 0.8 and P(A

**or**B) = 0.9 , determine P(B) If

a) A and B are independent

b) A and B are mutually exclusive

## Homework Equations

for Independence P(A and B) = P(A) x P(B)

for Mutually Exclusive P(A or B) = P(A) + P(B)

## The Attempt at a Solution

for A) just by the formula i can say that P(A and B) = P(A) x P(B)

but i don't see still how i can find P(B), the P(A or B) part is really confusing to me.