WTF Math?

Discussion in 'General Off-Topic Chat' started by amrboghdady, Aug 15, 2011.

  1. amrboghdady
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    amrboghdady Member

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    Ok, here is the equation, tell me why it does not work?

    3 guys go to a Hotel to rent a room.

    Clerk says its 30 bucks.

    Each guy gives the clerk 10 bucks [ 10x3=30 ]

    They go to room.

    Clerk finds his mistake and calls bellboy over.

    Tells bellboy, I overcharged these guys 5 dollars. Room is only 25 dollars. Take this 5 dollars to them.

    Ok, says bellboy and goes to guys room.

    After they answer door he explains they were over charged 5 dollars. [ 25 + 5 =30 ]

    Ok, say the guys, give us each back one dollar, and keep 2 for a tip to make it work out. [ 1+1+1+2=5 ]

    Bellboy does that and leaves with his 2 dollar tip.

    WTF math is happening. 25 + 5 =30 right? right.

    OK, now the 3 guys starting out paying 10 dollars each. They now each get back one dollar. [ 10 -1 = 9 ]

    Now they have only paid 9 dollars each and the bellboy got a 2 dollar tip.

    3 x 9 =27 plus the 2 the bellboy got = 29 dollars. WTF ? They started out with paying 30 dollars.

    If the math works one way, then why not the other? Imagine if this is a business transaction and the numbers are millions. Who gets the missing dollar?
     
  2. Narayan

    Narayan desu~

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    edit: wait, that doesn't work...

    okay, 2 paid $8 and one paid $9 = $25
    and the 5 dollars.

    edit: haha think you can fool me with saying each one paid $9, and adding the $2. if that's the case, you need to add the $3 too, then it would be $32.
     
  3. prowler

    prowler Sony

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    You lost me at equation.
     
  4. Nathan Drake

    Nathan Drake Obligations fulfilled, now I depart.

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    They each pay $10.

    10 10 10

    5 is taken. That is about $1.67 taken off per person. So that's about $8.33 paid per person.

    8.33 8.33 8.33

    That totals $25. They are then given $1 back each, and $2 is given to the bellhop.

    8.33 + 8.33 + 8.33 + 1 + 1 + 1 +2 = 30

    The problem was that when looked at collectively, the numbers are a little harder to see. Regardless, businesses are handled carefully and with far more than basic math skills.
     
  5. Zarcon

    Zarcon .:~Enigmatic Wanderer~:.

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  6. amrboghdady
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    amrboghdady Member

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    Haha, its really much simpler than that
    It took me a good while to figure it out, just to discover how easy it is

    They each paid $9, which sums to $27, that $27 already includes the $2 tips, so you need not add it again [​IMG]

    Hope I made it clear enough, cause all these numbers make it so complicated xD
     
  7. Shinigami357

    Shinigami357 Current "give a fuck" level: Honey Badger

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    Without having to resort to decimals and stuff [change? what's that? LOL], I think this question, and many more like it, are deliberately made just to make this conundrum.

    I think the thing that really makes questions like this is, as far as I remember, the number subtracted from the original tally is always prime. 5 is a prime number. We are then forced to divide it as equally as possible, but without resorting to decimals, in which case [because prime numbers cannot be divided by anything other than 1 and the number itself] we are left with a surplus on one side and a deficit on another. And thus, the whole thing evolve into a clusterf*ck [even if you mash B. LOL]

    That's my take on it.
     
  8. Snailface

    Snailface My frothing demand for 3ds homebrew is increasing

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    Here's a graph for the visual thinkers [​IMG] :
    [​IMG]
    The confusion* comes from the way it's explained. If you follow the numbers, things make sense.

    *This is what change artists prey on. [​IMG]
     
  9. Chikaku-chan

    Chikaku-chan ᏁᎽᎪ~

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    You lost me at "Ok,"
     
  10. pistone

    pistone GBAtemp Advanced Fan

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    this ^ ,or you can 5/3 and it comes out 1.66666666....7
    this 0.00000000....7 is the guilty as the number without this 0.0000000...7 cant become a full one (i dont know hot to write it in English hope its ok )
    for example 1 and say at 0.944444444444444444...3
     
  11. r3gR3t

    r3gR3t GBAtemp Regular

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    Ha, this brings back old memories [​IMG]
    The first time I saw this riddle was when I first played MMBN4 Red Sun and installed the 'Humor' program on MegaMan [​IMG]

    Anyways, I second what Shinigami357 said [​IMG]
     
  12. SinHarvest24

    SinHarvest24 Shiroyasha

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    This.


    Pretty nice teaser you got here but you'll need to up your game up for the temp. [​IMG]
     
  13. The_Dragons_Mast

    The_Dragons_Mast GBAtemp Advanced Fan

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    I cant really see how this is hard:P.
    1 guy payed a dollar more to the hotel than the other 2 while the other 2 each payed a dollar to the bellboy.
    What exactly doesn't make sense???
     
  14. chris888222

    chris888222 GBAtemp's Flygon Fan

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    This riddle is very famous...

    And it's not really math related, but rather logic. [​IMG]
     
  15. WigWrm

    WigWrm GBAtemp Regular

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    Nathan Drake explains it the best. Each person paid 1/3 of the bill. They got the 5 bucks back. They gave 2 to the bell boy. 25/3=8.333 repeating. Take the decimal from that number and multiply it by 3. There's your lost dollar.