2QUESTION 2 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
148
countries
How to estimate it
Fermi’s official “Napkin math”
There are about 200 countries in the world. Red shows up on flags more than any other color, it's bold and it reads from far away. Guess something like three in four flags use it.
- World countries
- ~200
- Flags with red (guess)
- × 75%
- 200 × 75%
- ≈ 150
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- National flags surveyed
- 192
- Flags of the World (FOTW), flags containing red
- 148 (77%)
Reference cited by Fermi: Flags of the World (FOTW), Statistics on Flag Colors
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.