All Fermi answers
Fermi #40 · Question 1

How many 3 oz (85 g) packets of Jell-O would it take to turn an Olympic swimming pool into Jell-O?

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.

Answer & explanation

Official answer

5,300,000

packets

How to estimate it

Fermi’s official “Napkin math”

An Olympic pool holds about 660,000 gallons. How much Jell-O does one box make? Two cups, and a gallon is 16 cups, so 8 boxes fill a gallon.

Pool volume
~660,000 gal
Boxes per gallon
× 8
660,000 × 8
≈ 5,300,000

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

Source calculation & reference
Olympic pool volume
≈ 660,000 gal (2,500,000 L)
One 3 oz box makes 4 half-cup servings
÷ 2 cups (0.47 L)
2,500,000 ÷ 0.47
≈ 5,300,000 packets

Reference cited by Fermi: Kraft Heinz Jell-O package directions (3 oz box, four 1/2-cup servings) · World Aquatics competition pool dimensions

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