Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
147
credit cards
How to estimate it
Fermi’s official “Napkin math”
The Starry Night is a living-room painting, nowhere near the size of a wall. Maybe 3 feet wide and 2 and a half tall. A credit card is about 3.5 by 2 inches, so how many fit across? About 10, and 15 down.
- Cards across 36 in
- 10
- Cards down 30 in
- × 15
- 10 × 15
- ≈ 150
The Starry Night is a living-room painting, nowhere near the size of a wall. Maybe a meter wide and 70 centimeters tall. A credit card is about 8.5 by 5.5 centimeters, so how many fit across? About 12, and 13 down.
- Cards across 1 m
- 12
- Cards down 70 cm
- × 13
- 12 × 13
- ≈ 156
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- The Starry Night (MoMA), 73.7 cm x 92.1 cm
- = 6,788 cm²
- One credit card (ISO/IEC 7810 ID-1), 8.56 cm x 5.40 cm
- ÷ 46.2 cm²
- 6,788 ÷ 46.2
- ≈ 147
Reference cited by Fermi: MoMA collection entry (oil on canvas, 73.7 x 92.1 cm) · ISO/IEC 7810 ID-1 card, 85.60 x 53.98 mm
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