Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
2,500,000
rivets
How to estimate it
Fermi’s official “Napkin math”
The tower is probably about 1,000 feet tall. There are rivets across nearly every surface since it was built before welding. Let's break it down to a smaller number, like how many rivets per 10 feet of tower? Way more on the bottom half (four legs) than the top. Maybe 25,000 rivets on average? That kinda checks out, there are a lot of rivets.
- Tower height
- ~1,000 ft
- 1,000 ÷ 10
- 100 sections
- Rivets per 10 ft
- ≈ 25,000
- 100 × 25,000
- ≈ 2,500,000
The tower is probably about 300 meters tall. There are rivets across nearly every surface since it was built before welding. Let's break it down to a smaller number, like how many rivets per 10 meters of tower? Way more on the bottom half (four legs) than the top. Maybe 100,000 rivets on average? That kinda checks out, there are a lot of rivets.
- Tower height
- ~300 m
- 300 ÷ 10
- 30 sections
- Rivets per 10 m
- ≈ 100,000
- 30 × 100,000
- ≈ 3,000,000
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Placed at the Levallois-Perret workshop, about two-thirds
- ≈ 1,700,000
- Placed on site, about one-third
- + ≈ 800,000
- Total in the metal structure (official site)
- ≈ 2,500,000
Reference cited by Fermi: Official Eiffel Tower site (SETE)
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