coverHere is the Friday puzzle!  Solution on Monday.

Imagine that you have a coin that is biased – that is, in a long series of tosses it won’t come up with 50% heads and 50% tails.  Alas, you don’t know the extent of the bias.  How can you use the coin to generate a random series of zeros and ones?

I have produced an ebook containing 101 of the previous Friday Puzzles! It is called PUZZLED and is available for the Kindle (UK here and USA here) and on the iBookstore (UK here in the USA here). You can try 101 of the puzzles for free here.