1QUESTION 1 OF 3
Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
7,700
M&Ms
How to estimate it
Fermi’s official “Napkin math”
A basketball holds about 7 liters inside. An M&M is tiny, under a cubic centimeter. Knock off about a third for the gaps between them.
- Basketball volume
- ~7,000 cm³
- Volume per M&M
- ÷ 0.6 cm³
- Knock off a third for gaps
- × 0.65
- 7,000 ÷ 0.6 × 0.65
- ≈ 7,600
A basketball holds about 400 cubic inches inside. How many M&M's pack into one cubic inch? Maybe 25, and knock off about a third for the gaps between them.
- Basketball volume
- ~400 in³
- M&M's per cubic inch
- × 25
- Knock off a third for gaps
- × 0.65
- 400 × 25 × 0.65
- ≈ 6,500
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Basketball interior (size 7)
- ≈ 7,240 cm³
- Volume of one M&M
- ÷ 0.64 cm³
- Packing efficiency (oblate)
- × 0.68
- 7,240 ÷ 0.64 × 0.68
- ≈ 7,700
Reference cited by Fermi: Spalding ball spec · Mars confectionery dimensions
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