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I wrote a Beats-per-Minute calculator. Tap any key to a beat and it will display the tempo. It’s a step above other implementations around the web because it shows correct precision and it changes color once it has an accurate reading. Try it!

You can turn a piece of paper into a sort of puzzle piece in just a few quick folds. With 6 pieces, you can make a cube. With 12 pieces or 30 pieces, you can make pointy stars. (Mathematicians call them stellated icosahedra.) Making the pieces is simple, and assembling them into these shapes is easier than it looks.

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I considered two questions about the board game Risk.

1. What are the odds of winning a particular dice roll? (like 3 dice vs. 2 dice, 3 dice vs. 1 die, etc.)
2. What are the odds of conquering a territory? (for example, 20 men invading 17 men)

Anyone who has played risk has an intuitive sense of the answers to the first question. Odds of winning a 3 dice vs. 2 dice battle are about 50/50. The invading army gets the advantage of an extra die, but ties go to the defender. It turns out that these advantages roughly balance each other out. (Full results.)

Question #2 is harder because battles between a large number of soldiers are complicated. It all comes down to who has to roll with a reduced number of dice. For example, if a large army is cut down early with a string of bad luck, its odds of winning go down much faster.

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With a giant glass pipe, a slice of ceramic cut from a diesel exhaust system, and a strip of toaster wire, I built an acoustical cannon: The Horn of Jericho. It is the brainchild of John Wight, a research scientist at Corning Incorporated, and it is probably unique. Read More to see better pics and video clip of the horn in action.

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Uno games can go on forever. Game length depends mainly on how the cards get shuffled. How long is an Uno game likely to take? Does including more players make a longer game or just more chances for someone to win and end it?

Sounds like the perfect way to squirm out of taking History of Mathematics by writing an independent paper about Uno! My musings here are brief and not math-y.

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