MHB Conditional Probability with 3 Events

AI Thread Summary
The discussion focuses on solving a conditional probability problem involving three events, A, B, and C. Key points include the application of the formula P(A|B) = P(A ∩ B) / P(B) to derive values for P(A|B), P(B'), and the odds in favor of B. The calculations reveal P(B) as 2/3, P(B') as 1/3, and odds in favor of B as 2 out of 5. The user expresses gratitude for the guidance received, indicating improved understanding ahead of an upcoming exam. Overall, the thread highlights the importance of foundational formulas in solving conditional probability problems.
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I'm currently stuck on a question that involves conditional probability with 3 events. This is a concept that I'm having the most trouble grasping and trying to solve in this subject. I am not sure how to start this problem.

The Question:
Given that P(A n B) = 0.4, P(A n C) = 0.2, P(B|A)=0.6 and P(B)=0.5, find the following.
a) P(A|B)
b) P (B')
c) P(A)
d) P (C|A)
e) the odds in favor of B

If someone could provide an explanation on how to solve this and guide me through it, that would be greatly appreciated! I really want to understand how to do problems like these.
 
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$P(A|B)= \frac{P(A\cap B)}{P(B)}$. You are given that $P(A|B)= 0.6$ and that $P(A\cap B)= 0.4$ so $0.6= \frac{.4}{P(B)}$. $P(B)= \frac{0.4}{0.6}= \frac{2}{3}$. "(e) the odds in favor of B" are "2 out of 5" and "(b) P(B')= 1- 2/3= 1/3".
 
Thanks for the fast reply! We have an exam on monday and I've been stuck on this all day and understand it better now!
 
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