Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
46
days
How to estimate it
Fermi’s official “Napkin math”
An Olympic pool holds about 660,000 gallons. How fast does a garden hose run? It fills a 5 gallon bucket in well under a minute, so call it 10 gallons a minute, which is 600 an hour.
- Pool volume
- ~660,000 gal
- Hose flow
- ÷ 600 gal/hour
- 660,000 ÷ 600
- ≈ 1,100 hours
- ÷ 24
- ≈ 46 days
An Olympic pool holds about 2.5 million liters. How fast does a garden hose run? It fills a 10 liter bucket in maybe 15 seconds, so call it 40 liters a minute, which is 2,400 an hour.
- Pool volume
- ~2,500,000 L
- Hose flow
- ÷ 2,400 L/hour
- 2,500,000 ÷ 2,400
- ≈ 1,040 hours
- ÷ 24
- ≈ 43 days
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Olympic pool volume
- ≈ 660,000 gal (2,500,000 L)
- Garden hose flow
- ÷ 10 gal/min
- 66,000 minutes
- ≈ 1,100 hours
- ÷ 24
- ≈ 46 days
Reference cited by Fermi: World Aquatics competition pool dimensions (50 × 25 × 2 m) · typical garden hose flow, 10 gal/min
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