Three people check into a hotel room that costs $30. They each pay $10. Later, the manager realizes there was a discount and the room actually cost $25. He gives the bellboy $5 to return to the guests. The dishonest bellboy pockets $2 and gives $1 back to each of the three guests. Now, each guest has paid $9 (total $27), and the bellboy has $2. That equals $29. Where is the missing dollar?
There is no missing dollar; the math mixes addition and subtraction incorrectly.
The $27 paid by the guests already includes the $2 kept by the bellboy ($25 for the room + $2 for the bellboy). Adding the bellboy's $2 to $27 is a logical fallacy; you should add the $3 returned to guests ($27 + $3 = $30 total 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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