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Mind-Bending Math & GamesExponential Growth

Rice on a Chessboard

Double a grain on every square and you'd bankrupt a kingdom

A king is asked for one grain of rice, then two, then four. He laughs at so little. How long until he stops laughing?

You'll find out

  • What the last square alone has to hold
  • Where the harmless part suddenly ends
  • What a chessboard has to do with chips

Why it matters

Savings, debts, viruses and chips all grow by doubling. Your gut reads doubling as a slow, steady climb. It isn't.

About 3 min6 interactive slides · 5 questionsLesson 145 · Zone 17

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