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Written by Erik C. Holm   
Thursday, 08 November 2012 00:00

Our project mission for the Web Math Projects Organization is to reinforce the fundamentals of mathematics through the use of interactive web technologies and Internet communications.  See our Mission Statement.

This Puzzle Developed By Erik C. Holm from Seattle

Here is the puzzle:

When choosing 2 teams from a group of 4 players we start with each player flipping a coin. The first flip could be all tails (a goocher) or all heads (a moon), this occurs 12.5% of the time and requires a reflip. After the first flip, if there is a 3-of-a-kind (odds 50%), then those three continue to flip till two are paired up (odds 75%),. During this convoluted choosing process there are two possibilities of entering into an infinite unending succession of flips. This process requires at least 4 coin flips, the odds of resolution with the first 4 flips is only 37.5% and the odds of entering a possible infinite loop is 25%.


1) Is there a simpler process using coin flips to make the choice?

  1. The odds of each team combination being equal

  2. No possible infinite successions

  3. The minimum amount of flips


2) There is a way to decide the teams fairly with one coin toss, what is it? (There is a hint within the preceding sentence. )

Last Updated on Friday, 20 March 2015 00:27