3QUESTION 3 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
67,000,000
pairs
How to estimate it
Fermi’s official “Napkin math”
The easiest place to start is the world's population, about 8 billion. How many new pairs does the average person get a year? Some people buy lots, plenty buy one or none. Call it 3.
- World population
- 8,000,000,000
- New pairs per person a year
- × 3
- Pairs a year
- ≈ 24,000,000,000
- 24B ÷ 365 days
- ≈ 66,000,000
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Pairs made worldwide in 2025
- 24,600,000,000
- Days in a year
- ÷ 365
- 24.6B ÷ 365
- ≈ 67,000,000
Reference cited by Fermi: APICCAPS World Footwear Yearbook 2026 (24.6 billion pairs produced in 2025)
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