3QUESTION 3 OF 3
Answer & explanation
Based on Chinese state media figures for 2024.
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
25,000,000,000
pairs
How to estimate it
Fermi’s official “Napkin math”
This question comes down to: on average, how many pairs of socks does a person go through in a year? Let's go with eight pairs. That's 64 billion pairs of socks (eight pairs times eight billion people). Divided by three you get just over 20 billion.
- People on Earth
- 8,000,000,000
- Pairs per person a year
- × 8
- A third of the world's socks
- ÷ 3
- 64B ÷ 3
- ≈ 21,000,000,000
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Datang subdistrict, reported yearly output (Xinhua, 2024)
- over 25 billion pairs
- Whole-city floor from the Zhuji government (end of 2024)
- over 20 billion pairs
- ≈
- 25,000,000,000
Reference cited by Fermi: Xinhua
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.