Suppose there are three cards: a black card that is black on both sides,
a white card that is white on both sides, and a mixed card that is black on one side and white on the other.
All the cards are placed into a hat and one is pulled at random
and placed on a table.
The side facing up is black.

What are the odds that the other side is also black?

There are 3 black sides, and 2 of them have a black on the other side, so the answer is 2/3.

Posted by Steve Herman on 2017-06-08 09:09:18