Can you help?

IraFrdmn@aol.com
Thu, 17 Apr 1997 11:29:58 -0400 (EDT)


A friend of mine gave me the following question. Ihope that you can give
the answer.

A jar contains one organ either a brain or a heart. An Alien puts a brain in
the jar. He then pulls out a brain. What`s the probability that the jar
originally contained a brain. I think that this is the "LETS MAKE A DEAL"
problem and I feel that the answer is 2/3 but then sometimes I think it is
3/4?