Fermi

How to play

1. 01

   Make your best guess

   You get three questions and one guess at each. Think “how many Oreos are eaten in the US each day?” A built-in calculator is there when you need it.

2. 02

   See how close you were

   The real answer is revealed, along with some example maths you could have used to get there.

3. 03

   Compare with friends

   Get your daily score, see how you did against everyone else who played, and share your result.

How scoring works

You're scored on how far off you were, as a multiple of the real answer. Lower is better, and your score for the day is the average of all three.

Why “Fermi”?

It's named after Fermi estimation, the technique of using quick maths and reasonable guesses to get close to hard-to-know numbers. Physicist Enrico Fermi famously estimated the strength of an atomic blast from how far scraps of paper flew from his hand.