2QUESTION 2 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
255
babies
How to estimate it
Fermi’s official “Napkin math”
Start with the world's 8 billion people. Everyone is born once, over a life of maybe 75 years, so around 100 million births a year. How many minutes in a year? About half a million, so spread the births across those.
- World population
- 8,000,000,000
- ÷ 75-year life
- ≈ 100M born/yr
- ÷ 525,600 minutes
- ≈ 200
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Annual global births
- ~134 M
- Minutes in a year
- ~525,600
- 134,000,000 ÷ 525,600
- ≈ 255
Reference cited by Fermi: UN World Population Prospects 2024
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