Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
2,400
US dollars
How to estimate it
Fermi’s official “Napkin math”
There are a few thousand billionaires, call it 3,000. How rich is a typical one? A handful are worth hundreds of billions, so maybe 5 billion each on average. Now split that across 8 billion people.
- Billionaires
- ~3,000
- Average fortune
- × $5 billion
- $15 trillion ÷ 8 billion people
- ≈ $1,900
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Combined net worth of Forbes' 3,428 billionaires (March 1, 2026)
- $20.1 trillion
- World population, March 2026 (UN World Population Prospects 2024)
- ÷ 8.28 billion
- ≈
- $2,400
Reference cited by Fermi: Forbes, The World's Billionaires 2026: 3,428 billionaires worth a combined $20.1 trillion (net worths as of March 1, 2026) · United Nations, World Population Prospects 2024: about 8.3 billion people in 2026
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