3QUESTION 3 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
3,200,000,000
iPhones
How to estimate it
Fermi’s official “Napkin math”
The iPhone launched in 2007, so it's been around about 19 years. Apple sells somewhere near 150 million a year, so multiply the two.
- Years since 2007
- ~19
- Sold per year
- ~150 million
- 19 × 150M
- ≈ 2.9 billion
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Apple's announced total (Q3 2025 earnings call, July 2025)
- 3 billion
- Sold since then, about 13 months at ~250 million a year
- ≈ 270 million
- 3 billion + 270 million
- ≈ 3.2 billion
Reference cited by Fermi: Apple Q3 2025 earnings call, July 2025
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