WTF Math?

Discussion in 'General Chat' started by globegenius, Aug 15, 2011.

  1. #1
    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?
     
    globegenius, Aug 15, 2011 IP
  2. deutsched

    deutsched Active Member

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    #2
    Haha, why are you adding 2 to the 27 when instead you're supposed to subtract the 2 from the 27 (27-2), it then becomes 25, which is the real room value :p
     
    deutsched, Aug 15, 2011 IP
  3. impress51

    impress51 Guest

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    #3
    simple mistake.. subtract the 2 not add it.. but the way you have put it.. stumped me for a bit its only coz deutsched said subtracting it.. then i realised
     
    impress51, Aug 16, 2011 IP
  4. impress51

    impress51 Guest

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    #4
    actually saying that though.. if they started paying 30 dollars.. where has the extra one gone.. i agree.. hes done the right thing by adding the 2 not subtracting it.. and there still is a dollar missing
     
    impress51, Aug 16, 2011 IP
  5. The Growbiss Services

    The Growbiss Services Peon

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    #5
    stumped me for a bit its only coz deutsched said subtracting it.
     
    The Growbiss Services, Aug 16, 2011 IP
  6. fokerss

    fokerss Active Member

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    #6
    the goverment get the dollar for tax , in the story is the hotel owner get the miss dollar . thats how the bussiness work.
     
    fokerss, Aug 16, 2011 IP
  7. deutsched

    deutsched Active Member

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    #7
    No, you should subtract the 2, cause they paid 30, then they get 3 back, so they paid 27, which already includes the tips of the guy (25 for room + 2 tips = 27)
     
    deutsched, Aug 16, 2011 IP
  8. Wulkanen

    Wulkanen Well-Known Member

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    #8
    In the beginning they each pay $10.

    10 + 10 + 10

    $5 is taken by mistake.
    That is about $1.67 taken off per person.
    So they should have paid about $8.33 per person.

    8.33 + 8.33 + 8.33
    That totals $25.

    They are then given $1 back each, and $2 is given to the bellboy.

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


    That wasn't so hard was it?
     
    Wulkanen, Aug 16, 2011 IP
  9. foodsurveys

    foodsurveys Peon

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    #9
    thats not the story though wulkanen.. coz they dont pay 8.33 .. they pay 9 each.. if they was to pay 8.33 then it would be as simple as your saying but they dont pay that..
     
    foodsurveys, Aug 17, 2011 IP
  10. Wulkanen

    Wulkanen Well-Known Member

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    #10
    Solving the problem practically
    1. Get a paper.
    2. Get a scissor.
    3. Cut the paper in 30 pieces.
    4. Put all pieces in 1 place.
    5. Take out 5 pieces (the $5).
    6. Put back 3 pieces (the $3 returned).

    Now you see that all the 30 pieces (dollars) are there.
    $28 are given to the ones who paid, $2 are given to the bellboy.

    7. Now sort the 28 pieces in to 3 stacks.
    8. You will notice that you will have 1 piece too many (hence the missing dollar that is equal to 0.333 in the math problem)

    So, $28/3 is not going to give you a integers. It's going to give you $9.333.
    Meaning that there is 0.333*3 = $1 that could not be split among all 3 persons.

    I hope you understand now.

    Feel free to repeat the solution yourself to verify that it's true. =)
     
    Wulkanen, Aug 17, 2011 IP
  11. neo127

    neo127 Active Member

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    #11
    And this, this 0.33, causing the whole trouble which is not literally paid to anyone. I must say that sometimes math makes me nuts.
     
    neo127, Aug 17, 2011 IP