This problem is adapted from an Oxford University admissions question. They say if you can solve this in your head, you are a genius ;)

Alex Bellos's column on The Guardian
https://www.theguardian.com/science/2...

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Book ratings are from June 2021.

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Mind Your Decisions: Five Book Compilation
https://amzn.to/2pbJ4wR
A collection of 5 books:
"The Joy of Game Theory" rated 4.2/5 stars on 200 reviews
http://amzn.to/1uQvA20
"The Irrationality Illusion: How To Make Smart Decisions And Overcome Bias" rated 4/5 stars on 17 reviews
http://amzn.to/1o3FaAg
"40 Paradoxes in Logic, Probability, and Game Theory" rated 4.1/5 stars on 30 reviews
http://amzn.to/1LOCI4U
"The Best Mental Math Tricks" rated 4.2/5 stars on 57 reviews
http://amzn.to/18maAdo
"Multiply Numbers By Drawing Lines" rated 4.1/5 stars on 23 reviews
http://amzn.to/XRm7M4

Mind Your Puzzles: Collection Of Volumes 1 To 3
https://amzn.to/2mMdrJr
A collection of 3 books:
"Math Puzzles Volume 1" rated 4.4/5 stars on 75 reviews
http://amzn.to/1GhUUSH
"Math Puzzles Volume 2" rated 4.3/5 stars on 21 reviews
http://amzn.to/1NKbyCs
"Math Puzzles Volume 3" rated 4.3/5 stars on 17 reviews
http://amzn.to/1NKbGlp

2017 Shorty Awards Nominee. Mind Your Decisions was nominated in the STEM category (Science, Technology, Engineering, and Math) along with eventual winner Bill Nye; finalists Adam Savage, Dr. Sandra Lee, Simone Giertz, Tim Peake, Unbox Therapy; and other nominees Elon Musk, Gizmoslip, Hope Jahren, Life Noggin, and Nerdwriter.

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