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Fermi question · Geography

About how many square kilometers does the Great Barrier Reef Marine Park cover?

Make a fast, defensible estimate before you reveal the reference answer. Think in factors, not exact recall.

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What is your estimate?

square kilometers

Use a positive number. Commas and scientific notation are okay.

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Reference answer

Reveal the reference answer

≈ 344 thousand square kilometers

Fermi estimates are judged by scale, so a reasonable approximation can still earn a strong score.

One way to estimate it

Compare the reef’s mapped area with the size of a large country.

  1. Australia comparisonReef is a few percent of Australia’s land area
  2. Australia area≈ 7.7M km²
  3. Estimate≈ 0.045 × 7.7M ≈ 350k km²

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