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I think this is close enough to a math question.

  1. Jan 17, 2007 #1
    So there are three guys fresh out of college who want to save money, so they decide to rent a room. The room costs 30 dollars, so they split it 10-10-10. They pay, but it turns out the room is only $25, so the manager asks the bellboy to take $5 and to give it back. The bellboy takes a 'tip' off the top, and gives back $3. So, the paid $9 each. 9*3=27. The bellboy has $2. 9*3+2=$29. Where is the last dollar?

    If you know the answer or have heard it before, a simple "oooh, i get it" will suffice. Please do not spoil it for others until they are just about ready to commit suicide.

    That is all.
  2. jcsd
  3. Jan 17, 2007 #2


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    Highlight to read: Why have you done 9*3+2=29? 9*3=27, the total amount paid (25 for the room, 2 to the bellboy), then each person gets one dollar back each, so this sums to 30.

    Note, we have a brainteasers forum.
  4. Jan 17, 2007 #3

    Gib Z

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    Yea i've seen this one before.
  5. Jan 18, 2007 #4
    Ohhh i get it...lol
  6. Jan 18, 2007 #5


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    You probably wont catch too many people around here with that one. :D
  7. Jan 18, 2007 #6
    i have heard it before. its a very widely known brain teaser.
  8. Jan 19, 2007 #7
    I think this is more of a tautology and not a maths problem.

    The original total cost of the room = $30.00.
    Upon review, the total cost of the room is now = $25.00.

    This leaves $5.00.

    If they bell man takes $2.00, there are $3.00 remaining.

    25.00+2.00 = 27 + 3 = 30.

    Unless I am an idiot, I don't see the dilemma. I am going to go find the solution to this and see if there is a trick or something -- it seems to straight forward to me (I have never seen this before).

    EDIT: can't seem to find this problem when I google it -- did you rewrite it?
    Last edited: Jan 19, 2007
  9. Jan 19, 2007 #8


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    Well, I'd never heard it before, but the "solution" is clear! Just like any other brain teaser, it's meant to catch you out and disguise the answer. However, as uart says, I don't think many mathematicians will be caught out by it!
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