Here’s a fantastic exercise in thinking about thinking: The Upshot at the NYT is hosting an interactive puzzle that pits you against every other person who attempts the puzzle. It’s... a bit of a mind game.

It’s a digitized twist on a classic problem from economics:

We are asking them – and you – to pick a number from 0 to 100, with that number representing your best guess of two-thirds of the average of all numbers chosen in the contest.

For example, if the average of all numbers is 62, you would win by picking 41. (No decimals or fractions in your numbers are allowed.) If the average is 39, you’d win by picking 26. If the average is 31, you’d win by picking 21.

Stop and think for a second. What is everyone else going to do?

Take a crack at it over at the NYT, then head back here to discuss your result—especially if you enjoy io9’s Sunday Puzzle series. I’m curious to hear whether people who solve brain teasers recreationally approach the NYT’s challenge differently than others.


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