Three people check into a hotel room that costs $30 total. They each pay $10. Later, the manager realizes there was a promotion and the room should only cost $25. He gives the bellhop $5 in single dollar bills to return to the guests. On the way up, the dishonest bellhop keeps $2 for himself and gives $1 back to each of the three guests. Now, each guest has paid $9 (total $27), and the bellhop has $2, which equals $29. Where did the missing $1 go?
There is no missing dollar; it is a math trick in how the totals are added.
The guests paid $27 total ($25 went to the room, and $2 kept by the bellhop). Adding the $2 the bellhop has to the $27 they paid is a false equation; you should add the bellhop's $2 to the $25 room cost to equal the $27 they actually spent.
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: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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