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Where is the dollar?

  1. Mar 15, 2008 #1
    3 Men Go Into A Motel. The Man Behind The
    Desk Said The Room Is $30

    So Each Man Paid $10 And Went To The Room.

    A While Later The Man Behind The Desk
    Realized The Room Was Only $25

    So He Sent The Bellboy To The 3 Guys'
    Room With $5.

    On The Way The Bellboy Couldn't Figure
    Out How To Split $5 Evenly Between 3 Men, So He Gave Each Man A $1 And
    Kept The Other $2 For Himself.

    This Meant That The 3 Men Each Paid $9
    For The Room, Which Is A Total Of $27, Add The $2 That The Bellboy
    Kept = $29.

    Where Is The Other Dollar?
  2. jcsd
  3. Mar 15, 2008 #2


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    Science Advisor

    The net amount paid by each man was $9.00 (making a total of 3x9 = $27.00 paid). The net amount received by the hotel staff is also $27.00 ($2.00 by the Bellboy plus $25.00 by the guy at the desk). So where exactly is the supposed the discrepency?
  4. Mar 15, 2008 #3


    User Avatar

    This is a variation of the $100 bank problem (a man deposits money into the bank, each time he counts his remaining balance, etc which adds up to $99 even though he had $100). Adding the $2 that the bellboy kept is fallacious for the reason above. The hotel kept $27 and returned $3, so the men paid $9 each. That adds up to $30.
  5. Mar 16, 2008 #4
    The men each paid US$9 for the room or US$27 total. The hotel got US$25 and the bellboy got US$2. 25 + 2 = 27. It's a trick question and the 30 is not the goal. Or you can say each man initially paid US$10 and had US$1 returned to them. 30 - 3 = 27 = 25 + 2.
  6. Mar 16, 2008 #5


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    Staff Emeritus
    Science Advisor

    I've heard this brain teaser a few times. Anyway, since the answer's been given three times, I think that may be enough!
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