Probabilities of A & B Occurrences in S

[bethanyd]

Homework Statement

Suppose that A and B are two events of a sample space S such that P(A) = 0.7, P(B) = 0.6 and P(AinterceptB) = 0.4.
What are the probabilities of the following:
1. A occurs and B does now
2. Exactly one of the two events occurs
3. Neither event occurs.

I have tried this but the issue I am having is that I'm confused by the wording. We didn't really do anything like this in class, so I have no examples which coincide. Any help?

Thank you!

 

[rock.freak667]

P(A/B)= p(AnB)/P(B) which is the probability that B occurs given that A has already occured
to find the Probabilities...write out the the probability that you have to find...e.g P(A or B occurring) etc...

 

[bethanyd]

Hey

Sorry, I meant, "A occurs but B does not"... Would that simply be P(A)?

 

[rock.freak667]

If P(A) means the probability that A occurs then for A to occur and B not to occur

then you'd want P(AnB')