Three diners order a meal totaling $25. They each pay $10, giving $30 to the waiter. The waiter keeps a $2 tip for himself and returns $1 to each diner. Now, each diner has paid $9 (totaling $27), and the waiter kept $2, making $29. What happened to the missing $1?
There is no missing dollar; the calculation improperly adds the tip to the total paid instead of subtracting it
The $27 paid by the patrons already includes the waiter's $2 tip ($25 meal + $2 tip = $27 total spent). Adding the $2 tip again to $27 is mathematically incorrect. The full $30 is accounted for by $25 for the meal, $2 for the waiter, and $3 returned to the diners.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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