2QUESTION 2 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
2,350
planes
How to estimate it
Fermi’s official “Napkin math”
Picture the runways at a huge airport. How often does something take off or land? Call it one every 40 seconds, around the clock. That works out to 90 an hour.
- Movements an hour
- ~90
- Hours in a day
- × 24
- 90 × 24
- ≈ 2,200
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- O'Hare aircraft operations, 2025
- 857,392
- Days in a year
- ÷ 365
- 857,392 ÷ 365
- ≈ 2,350 a day
Reference cited by Fermi: FAA preliminary 2025 data (O'Hare, 857,392 operations) and ACI world movement rankings
How close was your guess?
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