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Mind-Bending Math & GamesExponential Growth

The Lily Pad Riddle

If lilies double daily and cover the pond on day 30, when was it half full?

Lily pads on a pond double every day, and on day 30 they cover it all. When would you have sounded the alarm?

You'll find out

  • Why your gut gets this riddle wrong
  • How late a problem starts to look big
  • A shortcut for anything that doubles

Why it matters

Outbreaks and debts grow like these lilies: they look harmless for most of the story, then take over in days.

About 3 min6 interactive slides · 5 questionsLesson 147 · Zone 17

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