1QUESTION 1 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
900,000
people
Source calculation & reference
- World population
- 8,200,000,000
- Adults are ~76%, half of them men
- ≈ 3,100,000,000
- Men taller than 6'6" (198 cm)
- ≈ 1 in 3,500
- 3,100,000,000 ÷ 3,500
- ≈ 900,000
Reference cited by Fermi: Derived: NCD-RisC country mean adult heights (2019) with a 7 cm spread, weighted by UN World Population Prospects (2024). No authority publishes a direct count.
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.