You want to cut a tortilla into 8 pieces. What's the minimum number of cuts you need to make? Is it statistically harder to guess an iPhone password that uses 3-digits or one that uses 4 unique digits? Two friends agree to meet up in a bar between midnight and 1 am. Each arrives at a random time and will wait 10 minutes for the other to show before leaving. What is the probability the two will meet at the bar? What if they are playing strategically? The YouTube channel and blog Mind Your Decisions has millions of views for math videos and posts. This book is a compilation of 70 of the best puzzles, divided into 25 classic puzzles in counting and geometry, 25 probability puzzles, and 20 game theory puzzles.