All Fermi answers
Fermi #110 · Question 3

How much money is 100 kg (220 lb) of $100 bills?

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

3QUESTION 3 OF 3

Answer & explanation

Canadian $100 bills, in Canadian dollars

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

Answer & explanation

Official answer

10,000,000

dollars

How to estimate it

Fermi’s official “Napkin math”

Banks bundle bills into stacks of 100, which is $10,000 in hundreds. How heavy is a stack? I have definitely never held one but I can imagine, maybe a 1/4 pound.

220 lb ÷ ¼ lb a stack
≈ 880 stacks
Each stack
× $10,000
880 × $10,000
≈ $8,800,000

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

Source calculation & reference
100 kg of bills ÷ 1 g each (Canadian polymer $100)
= 100,000 bills
Face value of each bill
× $100
100,000 × $100
= $10,000,000

Reference cited by Fermi: Bank of Canada

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