1QUESTION 1 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
25,400
full moons
How to estimate it
Fermi’s official “Napkin math”
Start with how long ago Cleopatra lived. She knew Julius Caesar, so call it about 2,000 years. How many full moons in a year? About one a month, so 12.
- Since Cleopatra
- ~2,000 yrs
- Full moons a year
- × 12
- 2,000 × 12
- ≈ 24,000
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Cleopatra dies (Britannica)
- Aug 10 or 12, 30 BC
- Days to Sept 15, 2026
- ≈ 750,600
- Synodic month (NASA)
- ÷ 29.53 days
- 750,600 ÷ 29.53
- ≈ 25,400
Reference cited by Fermi: Encyclopaedia Britannica for the date of death · NASA for the 29.53-day synodic month
How close was your guess?
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