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The 1089 Trick

Any three-digit number leads to the same answer

Pick any three-digit number. A stranger who never sees it already knows what four simple moves will turn it into. How?

You'll find out

  • Why the middle digit never matters
  • The nine numbers hiding in between
  • What happens with four digits

Why it matters

Magic tricks like this one are algebra in disguise: the way numbers are written doing what it cannot help doing.

About 3 min6 interactive slides · 5 questionsLesson 156 · Zone 18

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