# Read This Before Placing Any Bet: The Odds In A Coin Flip Are Not 50/50

Persi Diaconis, a math professor at Stanford, determined that in a coin flip, the side that was originally facing up will return to that same position 51% of the time. That means that if a coin is tossed with its heads facing up, it will land the same way 51 out of 100 times.

This is because no matter how a coin is flipped, the side that started up will spend more time facing up than the other one.

But things get more exciting when we talk about a spinning penny: (the article continues after the ad)

Because the heads on a penny (the side with Abraham Lincoln) is heavier than the other side, the coin’s center of mass will lie towards the heads side. Therefore, a flipping a penny will land tails side up roughly… wait for it… 80% of the time!

So now you know.

### If you like what you read, then you will definitely love this one: Which Is The Best Way To Shuffle A Deck Of Cards?

Photo: Nicu Buculei / Flickr

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