3QUESTION 3 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
1,600
letters
How to estimate it
Fermi’s official “Napkin math”
The easiest place to start is the number of countries, about 200. How long is a typical country name? Something like Kenya, Portugal, Colombia. Call it 8 letters.
- Countries on Earth
- ≈ 200
- Letters in a typical name
- ≈ 8
- 200 × 8
- ≈ 1,600
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Countries counted (193 UN members + Holy See + Palestine)
- 195
- Common short-form English names, letters only
- spaces and hyphens excluded
- Average per name
- ≈ 8.2 letters
- Total
- = 1,600
Reference cited by Fermi: United Nations list of member and observer states, letters counted across their common short-form English names
How close was your guess?
Your comparison will appear here.
Compare by ratio: divide the larger number by the smaller one. The closer to 1×, the better.