3QUESTION 3 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
500,000
snakes
How to estimate it
Fermi’s official “Napkin math”
The easiest place to start is England's population, about 56 million. How many of them keep a pet snake? More than you'd think, reptiles have really caught on. Maybe 1 in every 100 people.
- England population
- 56,000,000
- Keep a pet snake
- ~1 in 100
- 56M ÷ 100
- ≈ 560,000
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- UK pet snakes (UK Pet Food, January 2026)
- ≈ 600,000
- England share of UK population
- × 84%
- 600,000 × 0.84
- ≈ 500,000
Reference cited by Fermi: UK Pet Food, UK pet population data, January 2026 survey (about 600,000 pet snakes, kept in 1.3% of UK households)
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.