Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
880
fingers and thumbs
How to estimate it
Fermi’s official “Napkin math”
How many seats fit upstairs on a double-decker? Maybe 10 rows of 4, so 40. Downstairs the doors and stairs eat room, so call it 20 seats plus 20 people standing. And don't forget the driver.
- Upstairs seats
- ≈ 40
- Downstairs, seated and standing
- + 40
- Driver
- + 1
- 81 people × 10
- ≈ 810
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Seats, 40 upstairs + 22 downstairs
- 62
- Standing, lower deck only
- + 25
- Official capacity
- 87 passengers
- Driver
- + 1
- 88 people × 10 fingers and thumbs
- 880
Reference cited by Fermi: Mayor of London answer at Mayor's Question Time, for Transport for London: the New Routemaster seats 40 upstairs and 22 downstairs with 25 standing, an overall capacity of 87
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