Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
40
gallons
How to estimate it
Fermi’s official “Napkin math”
Maple syrup is super sweet, over half sugar at least. Sap isn't nearly that sweet. How much sugar is in it? Maybe 2%. So it has to be cooked down about 25 times, which means you start with 25 times as much.
- Sugar in syrup
- ~50%
- Sugar in sap
- ≈ 2%
- Cooked down
- ≈ 25 times
- 1 gallon × 25
- ≈ 25 gal
Maple syrup is very sweet, over half sugar. Sap is not nearly that sugary. How much sugar is in it? Maybe 2%. So it has to be cooked down about 25 times, and the jug holds about 4 liters.
- Sugar in syrup
- ~50%
- Sugar in sap
- ≈ 2%
- Cooked down
- ≈ 25 times
- 4 L × 25
- ≈ 100 L
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Rule of 86: 86 ÷ sap sugar %, at 2% sugar
- ≈ 43 gal
- Same rule at 2.5% sugar
- ≈ 35 gal
- Usual rule of thumb for producers
- ≈ 40 gal
- ≈
- 40
Reference cited by Fermi: Iowa State Extension: 43 gal at 2% sugar · NASDA maple survey training: about 40 gal
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