This puzzle went viral in the discrete mathematics community because so many people got it wrong! You roll a fair dice until you get a 6. What is the expected number of rolls, including the roll of 6, conditioned on the event that all previous rolls (if any) were even numbers? Gil Kalai did a survey on his blog that covers graduate level mathematics, and only about 18 percent guessed correctly. Over 50 percent chose the same wrong answer. Can you figure it this counter-intuitive puzzle?

My blog post for this video
https://wp.me/p6aMk-5jL

Oxford Dictionary of English definition and usage for dice
https://en.oxforddictionaries.com/definition/dice
(*In the video I incorrectly said "Oxford English Dictionary" which turns out to be a whole other thing. The definition quoted is correct as it comes from the dictionary that explains current language and practical usage---http://public.oed.com/about/th....e-oed-and-oxford-dic

Gil Kalai blog test your intuition (puzzle and poll)
https://gilkalai.wordpress.com..../2017/09/07/tyi-30-e

This puzzle is credited to credit to Elchanan Mossel. via Gil Kalai blog solution
https://gilkalai.wordpress.com..../2017/09/08/elchanan

Puzzling StackExchange
https://puzzling.stackexchange.....com/questions/54974

Math With Bad Drawings - A Probability Puzzle That You’ll Get Wrong
https://mathwithbaddrawings.co....m/2017/09/25/a-proba

*The Puzzling StackExchange post was removed (I am not sure why). Here is another discussion:
https://math.stackexchange.com..../questions/2463768/u

And another explanation:
http://www.yichijin.com/files/elchanan.pdf

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My Books

"The Joy of Game Theory" shows how you can use math to out-think your competition. (rated 3.8/5 stars on 30 reviews) https://www.amazon.com/gp/product/1500497444

"The Irrationality Illusion: How To Make Smart Decisions And Overcome Bias" is a handbook that explains the many ways we are biased about decision-making and offers techniques to make smart decisions. (rated 5/5 stars on 2 reviews) https://www.amazon.com/gp/product/1523231467/

"Math Puzzles Volume 1" features classic brain teasers and riddles with complete solutions for problems in counting, geometry, probability, and game theory. Volume 1 is rated 4.4/5 stars on 13 reviews. https://www.amazon.com/gp/product/1517421624/

"Math Puzzles Volume 2" is a sequel book with more great problems. (rated 5/5 stars on 3 reviews) https://www.amazon.com/gp/product/1517531624/

"Math Puzzles Volume 3" is the third in the series. (rated 3.8/5 stars on 4 reviews) https://www.amazon.com/gp/product/1517596351/

"40 Paradoxes in Logic, Probability, and Game Theory" contains thought-provoking and counter-intuitive results. (rated 4.3/5 stars on 12 reviews) https://www.amazon.com/gp/product/1517319307/

"The Best Mental Math Tricks" teaches how you can look like a math genius by solving problems in your head (rated 4.7/5 stars on 4 reviews) https://www.amazon.com/gp/product/150779651X/

"Multiply Numbers By Drawing Lines" This book is a reference guide for my video that has over 1 million views on a geometric method to multiply numbers. (rated 5/5 stars on 3 reviews) https://www.amazon.com/gp/product/1500866148/