Thread: Queen's Heads Puzzle
View Single Post
Old 07-21-2010, 01:31 PM   #12
pdurrant
The Grand Mouse 高貴的老鼠
pdurrant ought to be getting tired of karma fortunes by now.pdurrant ought to be getting tired of karma fortunes by now.pdurrant ought to be getting tired of karma fortunes by now.pdurrant ought to be getting tired of karma fortunes by now.pdurrant ought to be getting tired of karma fortunes by now.pdurrant ought to be getting tired of karma fortunes by now.pdurrant ought to be getting tired of karma fortunes by now.pdurrant ought to be getting tired of karma fortunes by now.pdurrant ought to be getting tired of karma fortunes by now.pdurrant ought to be getting tired of karma fortunes by now.pdurrant ought to be getting tired of karma fortunes by now.
 
pdurrant's Avatar
 
Posts: 73,644
Karma: 315126578
Join Date: Jul 2007
Location: Norfolk, England
Device: Kindle Oasis
Quote:
Originally Posted by omk3 View Post
Spoiler:
I pick up my 21 coins at random. I have x heads, and 21-x tails.
The gaoler has 21-x heads.
If I flip all my coins over, I now have 21-x heads, and x tails.
So I will always have the same number of heads as the gaoler, and always go free. Yay!
Exactly right, and nicely explained.
pdurrant is offline   Reply With Quote