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Mind-Bending Math & GamesArithmetic

The Missing Dollar

A famous money riddle works by adding the wrong things

Three guests pay 30 dollars, get 3 back, and the bellhop keeps 2. So why does the count stop at 29?

You'll find out

  • Where each of the 30 dollars really is
  • What is wrong with the riddle's sum
  • Why other prices spoil the trick

Why it matters

Bills, budgets and statistics hide the same mistake: numbers that sound related but do not belong in one sum.

About 3 min6 interactive slides · 5 questionsLesson 163 · Zone 19

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