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Data & ProbabilityStatistics

What ‘70% Chance of Rain’ Means

It isn't 70% of the day or 70% of the city

The forecast said 30% and you got soaked. Was the forecaster wrong, or have you been reading that number wrong all along?

You'll find out

  • What the percentage really counts
  • How a forecaster gets a grade
  • Why being right isn't enough

Why it matters

The same test tells you whether to trust a weather app, a doctor's odds or an AI that says it is sure.

About 3 min6 interactive slides · 5 questionsLesson 131 · Zone 15

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