Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
66,000
beans
How to estimate it
Fermi’s official “Napkin math”
An oil barrel holds 42 gallons. How far does a 1 pound bag of coffee go? Maybe 4 pots, about 2 gallons, so the barrel takes about 20 pounds. And how many beans are in a bag? A few thousand, call it 3,000.
- Oil barrel
- 42 gal
- A 1 lb bag brews ~2 gal
- ≈ 20 lb
- Beans in a 1 lb bag
- × 3,000
- 20 × 3,000
- ≈ 60,000
The barrel holds about 160 liters. How much coffee goes into a liter? A couple of big spoonfuls per mug and 4 mugs to the liter, so call it 50 grams. A bean weighs next to nothing, maybe 8 to the gram.
- Oil barrel
- ~160 L
- Coffee per liter, 50 g
- ≈ 8,000 g
- Beans per gram
- × 8
- 8,000 × 8
- ≈ 64,000
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Oil barrel, 42 US gallons (NIST)
- 159 L
- SCA Golden Cup brew ratio, 55 g per liter
- ≈ 8,745 g of coffee
- One roasted bean
- ÷ 0.1325 g
- 159 × 55 ÷ 0.1325 = 65,994, rounded
- ≈ 66,000
Reference cited by Fermi: Specialty Coffee Association Golden Cup Standard (55 g of coffee per liter of water) · NIST definition of the petroleum barrel (42 US gallons) · Honest Coffee Guide, average roasted bean weight
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