The Cab Problem

[PrayingMantis]

I haven't seen this problem discussed here. If it was - I apologize. There seem to be some different opinions with regard to the solution.

A cab was involved in a hit and run accident. Two cab companies, the Green and the Blue, operate in the city. You know that:

(a) 85% of the cabs in the city are Green; 15% are Blue.
(b) a witness says the cab involved was Blue.
(c) when tested, the witness correctly identified the two colors 80% of the time.

The question is, How probable is it that the cab involved in the accident was Blue, as the witness reported, rather than Green?