Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
70
sticky notes
How to estimate it
Fermi’s official “Napkin math”
The Mona Lisa is famously smaller than people expect, closer to a poster than a wall. Call it 30 inches tall and 20 across. A sticky note is 3 inches square, so how many fit down the long side? Ten, and seven across.
- Notes down the painting
- 10
- Notes across
- × 7
- 10 × 7
- ≈ 70
The Mona Lisa is famously smaller than people expect, closer to a poster than a wall. Call it 75 centimeters tall and 50 across. A sticky note is about 7.5 centimeters square, so how many fit down the long side? Ten, and seven across.
- Notes down the painting
- 10
- Notes across
- × 7
- 10 × 7
- ≈ 70
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Mona Lisa panel (Louvre), 77 cm x 53 cm
- = 4,081 cm²
- One sticky note, 7.6 cm square
- ÷ 57.8 cm²
- 4,081 ÷ 57.8
- ≈ 70
Reference cited by Fermi: Louvre catalogue entry for the Mona Lisa (oil on poplar, 77 x 53 cm) and 3M's standard Post-it sheet, 3 x 3 in (76 x 76 mm)
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