All Fermi answers
Fermi #62 · Question 1

How many kiwifruit would it take to weigh as much as an adult North Island brown kiwi?

Explore the official answer and the simple reasoning behind this Fermi estimate.

1QUESTION 1 OF 3

Answer & explanation

The official answer, with Fermi’s reasoning step by step.

A brown kiwi

A brown kiwi

A brown kiwi bird with a long pale beak, standing on the forest floor.

Illustration from Fermi.gg

Answer & explanation

Official answer

25

kiwifruit

How to estimate it

Fermi’s official “Napkin math”

A kiwi bird is about the size of a chicken. How heavy is that? Maybe 2.5 kilograms, so 2,500 grams. A kiwifruit sits in your palm, call it 100 grams.

Kiwi bird
~2,500 g
One kiwifruit
~100 g
2,500 ÷ 100
≈ 25

Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.

Source calculation & reference
Adult North Island brown kiwi, midpoint of male 2 kg and female 2.7 kg
≈ 2,350 g
Average Zespri Green kiwifruit
÷ 92.5 g
2,350 ÷ 92.5
≈ 25

Reference cited by Fermi: New Zealand Birds Online (Te Papa and Birds New Zealand), North Island brown kiwi: 2 kg male, 2.7 kg female · Zespri, average Green kiwifruit weight of 92.5 g

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