Suppose there are two bags A and B and a set of colored balls (red and green).
Partially color-blind people are told to place all the red balls in A and the green balls in B.
Their ability to distinguish the balls is 80% reliable.
15% of the balls are red, the rest green. (85%)
If we randomly choose a ball from bag A, what is the probability of it being red? (or green)?
We know that P(R) = .15, P(G) = .85.
I think we need something like P(R|A) = ?
Not sure how to proceed
EDIT: Ah! I think I see. I think that P(A | R) = .8 and P(B|R)=.2, etc... is that right?
EDIT 2: Hmm.. no, still not sure what P(A) should be though...