Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
940
bananas
How to estimate it
Fermi’s official “Napkin math”
How heavy is a wild silverback? About as much as two big men, so maybe 200 kilograms. A banana with its peel on is maybe 200 grams.
- Silverback
- ~200 kg
- In grams
- ≈ 200,000 g
- One banana
- ÷ 200 g
- 200,000 ÷ 200
- ≈ 1,000
How heavy is a wild silverback? About as much as two big men, so maybe 400 pounds. Bananas come about 3 to a pound at the store.
- Silverback
- ~400 lb
- Bananas per pound
- × 3
- 400 × 3
- ≈ 1,200
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Wild adult male western lowland gorilla (Smith and Jungers 1997, as given by SeaWorld)
- ≈ 169.5 kg
- Whole ripe Cavendish banana, peel included (Soltani et al. 2011)
- ÷ 180.6 g
- 169,500 ÷ 180.6
- ≈ 940
Reference cited by Fermi: SeaWorld Parks gorilla fact sheet: wild adult male western lowland gorillas weigh about 169.5 kg (374 lb) · Soltani, Alimardani and Omid (2011), physical properties of full-ripe Cavendish bananas: 180.56 g whole fruit
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