3QUESTION 3 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
12,000,000
plates
How to estimate it
Fermi’s official “Napkin math”
Start with Japan, about 125 million people. How often does someone go for conveyor-belt sushi? Maybe every few months, call it 4 times a year, and about 10 plates a trip.
- Japan population
- 125,000,000
- Visits per person per year
- × 4
- Plates per visit
- × 10
- 125M × 4 × 10 ÷ 365
- ≈ 14 million
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Japan conveyor-belt sushi sales, 2024
- ≈ ¥831.8 billion
- Average spend per person per visit
- ÷ ¥1,940
- Plates eaten per visit
- × 9.9
- Per day (÷ 365)
- ≈ 12 million
Reference cited by Fermi: Fuji Keizai conveyor-belt sushi market survey (2024) · Maruha Nichiro conveyor-belt sushi consumer survey 2025
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