Question with intersects and complements.

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The discussion revolves around calculating the probability P((A∩B)∪(A∩C)) given specific probabilities for events A, B, and C. The user initially identifies that P(A∩B∩C) = 0, indicating mutual exclusivity among the events. They express confusion about how to utilize the complements P(A∩B^c) and P(A∩C^c) effectively in their calculations. After some back-and-forth, it is confirmed that the user's approach to the problem is correct, and they are encouraged to proceed with their calculations. The conversation highlights the importance of understanding probability intersections and unions in solving such problems.
Shawj02
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Ok, first post.
So I have this question, which goes something like this...
Given
P(A)=0.3, P(B)=0.3, P(C)=0.7
P(AnB^c)=0.2, P(AnC^c)=0.2, P(AnBnC)=0

Find P((AnB)U(AnC))

(Where; n =intersect, U union, ^c = complement.)

Personally my thoughts are..
P(AnBnC)=0. Therefore mutually exclusive.

And then Because probability cannot be negative. I think that leads to P(AnB)=0,P(AnC)=0 & p(BnC)=0.
Which couldn't be right, As that would give P((AnB)U(AnC)) = 0U0 = 0.

My major concern is how do I change P(AnC^c) & P(AnB^c) to something useful!

Thanks!
 
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Ive got
P(A)- P(AnB^c) + P(A)- P(AnC^c)= P((AnB)U(AnC))

Anyone want to double check me?
 
Shawj02 said:
Ive got
P(A)- P(AnB^c) + P(A)- P(AnC^c)= P((AnB)U(AnC))

Anyone want to double check me?


It's correct. Do you understand how? Also you obviously can get a number from it.
 
Awesome. Yeah, I understand how. Just had a block a guess.
Thanks.
 
I was reading a Bachelor thesis on Peano Arithmetic (PA). PA has the following axioms (not including the induction schema): $$\begin{align} & (A1) ~~~~ \forall x \neg (x + 1 = 0) \nonumber \\ & (A2) ~~~~ \forall xy (x + 1 =y + 1 \to x = y) \nonumber \\ & (A3) ~~~~ \forall x (x + 0 = x) \nonumber \\ & (A4) ~~~~ \forall xy (x + (y +1) = (x + y ) + 1) \nonumber \\ & (A5) ~~~~ \forall x (x \cdot 0 = 0) \nonumber \\ & (A6) ~~~~ \forall xy (x \cdot (y + 1) = (x \cdot y) + x) \nonumber...
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