Three friends split a restaurant bill evenly. Each pays $10. The manager realizes they overpaid and gives the waiter $5 to return to them. The waiter pockets a $2 tip and gives $1 back to each friend. Now, each friend has paid $9 (total $27), and the waiter has $2. That equals $29. Where did the missing dollar go?
There is no missing dollar
This is a classic fallacy. You should add the waiter's $2 to the $27 paid (getting $29, which equals the $25 to the restaurant + $4 returned/kept), not add the waiter's tip to the amount paid.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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