Fermi question · Everyday

If a resting adult’s pulse is 80 beats per minute, about how many times does the heart beat in 24 hours?

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?

beats per day

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

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Reference answer

Reveal the reference answer

≈ 115 thousand beats per day

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

One way to estimate it

Scale a plausible resting pulse across the minutes in a day.

  1. Minutes per day24 × 60 = 1,440
  2. Pulse80 beats/minute
  3. Estimate1,440 × 80 = 115,200 beats/day

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