2QUESTION 2 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
18
days
How to estimate it
Fermi’s official “Napkin math”
The Moon is about 240,000 miles away. How fast does a jet cruise? Around 550 mph. Divide for the hours, then turn that into days.
- Distance to the Moon
- ~240,000 mi
- Jet cruise speed
- ÷ 550 mph
- 240k ÷ 550
- ≈ 440 hrs
- ÷ 24
- ≈ 18 days
The Moon is about 380,000 kilometers away. How fast does a jet cruise? Around 900 kilometers an hour. Divide for the hours, then turn that into days.
- Distance to the Moon
- ~380,000 km
- Jet cruise speed
- ÷ 900 km/h
- 380k ÷ 900
- ≈ 420 hrs
- ÷ 24
- ≈ 18 days
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Distance Earth → Moon (avg.)
- ~384,400 km
- Cruise speed (e.g. 747)
- ~900 km/h
- 384,400 ÷ 900
- ≈ 427 hours
- ÷ 24
- ≈ 18 days
Reference cited by Fermi: NASA mean lunar distance · Boeing cruise specs
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