Hi this is Presh Talwalkar How predictable are you? Lets find out in this video. In front of you are the numbers 1 through 16 To get started, I want you to pick a number You can pick any of these sixteen numbers But you should remember which number you’ve picked It might help if you circled it as you’ll need to remember this number for the rest of the video. Now I want you to pick a second number. And I want one condition: I want that number to be in a different row and a different column from the first number you’ve picked. So if you picked the number 10 as your first number, the next number you pick should not be in the same row, and it should not be in the same column. So you can pick from any of the remaining numbers that are not in the same row and the same column as the first number you’ve picked I also want you to remember this number so remember the first number you’ve picked and the second number you’ve picked You’re gonna repeat this process: pick a third number that’s in a different row and a different column from the first two numbers you’ve picked. So you don’t want this number to be in the same row or the same column as either of the first two numbers you’ve picked. So now you’ve picked THREE different numbers and I want you to remember them because you’re gonna have to do one more thing I want you to pick a fourth number that’s also in a different row and in a different column. from the previous three number you’ve picked. So if you’ve followed along correctly, you’ve now picked FOUR numbers, and you played according to the rules where they are in different rows or in different columns so your numbers might end up looking something like this. So you’ve got your four numbers and I want you to ADD up these four numbers so there’s no way I could’ve known what first number you’ve picked, or the second number was, or third or the fourth. But now here comes a prediction. Add up those four numbers you have and here is what my prediction is: My prediction is the sum of your numbers is 34. Am I correct? If you want to know how this trick works, you can follow a link in the video description where I describe the mathematical proof in a blog post. Thanks for watching this video please subscribe to my channel, I make videos on math and game theory, you can catch me on my blog: MindYourDecisions which you can follow on Facebook, Google+ and Patreon. You can catch me on social media @PreshTalwalkar And if you like the video, please check out my books There is a detailed description of each book in the video description.