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Math Brain Teaser

  1. Apr 11, 2008 #1
    Three people check into a hotel. They pay $30 to the manager and go to their room. The manager finds out that the room rate is $25 and gives $5 to the bellboy to return. On the way to the room, the bellboy reasons that $5 would be difficult to share among three people, so he pockets $2 and gives $1 to each person. Now, each person paid $10 and got back $1. So they paid $9 each, totalling $27. The bellboy has $2, totalling $29. Where is the remaining dollar?
  2. jcsd
  3. Apr 11, 2008 #2


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    Gold Member

    "Paid" = apples
    "has" = oranges
    oranges can only be added to oranges
  4. Apr 11, 2008 #3
    Count how much money each person started with and how much each person ends up with.
  5. Apr 12, 2008 #4


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    You know how to read obscured text, right? Select the word "Hint:" - and everything after it....
  6. Apr 16, 2008 #5
    This is actually really simple...

    Explanation in white.

    This is a trick, really. There are thirty dollars in total. The bellboy takes two, leaving twenty eight dollars. He then gives one to each of the three, leaving twenty five dollars that have been paid. Each person PAYS $9, totaling $27, and then the bellboy takes $2 from that, leaving $25. In total, they paid $25 to the hotel and $2 to the bellboy -- which is $27 total, hence they paid $9 each. The extra three dollars they got in return are invisible, they paid $27 total ($2 to the bell boy, $25 to the rooms,) and now have an extra $1 to pocket.
    Last edited: Apr 16, 2008
  7. Jul 22, 2008 #6
    the answer is much simpler than anyone thinks, its just a trick as far as the wording goes. there are two ways to solve this.
    1. with math its quite simple. they payed 25 dollars so 25/3 = ($8.333... + 1 [the one they got back]) x 3people = $28 and the bellboy has 2 so thats 30$

    2. simple really... the bellboy has 2, the people have 3, and the manager has 25 which in total is 30
    Last edited by a moderator: Jul 22, 2008
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