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Red Marble, Blue Marble

The suggested solution is pretty good, but, I can give you a solution that makes it 100% likely for the first 15-20 pics.

The riddle said that you can arange the marbles any way you want.  So, simply, put half of the blue marbles in each jar, then cover them up with half of the red marbles.  Until you select enough marbles from anyone of the jars to start revealing the blue marbles, you will have a 100% chance of picking a red.

Shortly after that, it switches to 100% blue.  It just depends on how long you want to keep picking.  If you keep picking marbles, the average approaches 50% - just like ANY other solution.

David Lanouette
Saturday, January 04, 2003

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