All Fermi answers
Fermi #32 · Question 1

How many decks would it take to tile a basketball court with playing cards?

Explore the official answer and the simple reasoning behind this Fermi estimate.

1QUESTION 1 OF 3

Answer & explanation

Standard 52 Card Bicycle Deck

The official answer, with Fermi’s reasoning step by step.

Answer & explanation

Official answer

1,490

decks

How to estimate it

Fermi’s official “Napkin math”

An NBA court is 94 by 50 feet, so call it 4,700 square feet. How many cards cover a square foot? A card is 2.5 by 3.5 inches, so about four across and three and a half down. Call it 16. A deck holds 52.

Court area
~4,700 ft²
Cards per square foot
× 16
Cards needed
~75,000
÷ 52 per deck
≈ 1,450

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

Source calculation & reference
NBA court area
94 × 50 = 4,700 ft²
Convert to in²
× 144 = 676,800 in²
Card area
2.5 × 3.5 = 8.75 in²
Cards needed
≈ 77,300
÷ 52 per deck
≈ 1,490

Reference cited by Fermi: NBA court spec · poker card dimensions

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