Where is the 1 $??

Discussion in 'Odds & Ends' started by billnepill, May 9, 2011.

  1. billnepill

    billnepill Hall of Fame

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    (Inspired by the simple equation thread that is already 50+ pages, lol)

    Suppose 3 people go to a restaurant. The bill is 30 $. Each pays 10 $. The manager notices they are regular customers and decides to give them 5 $ back. The three take 1 $ each and give 2 $ tip to the waiter.

    Because they take 1 $ back, they in fact pay 9 $ each, right?

    But 9 + 9 + 9 equals 27 $ + the tip of 2 $ = 29 $ total.

    The bill was 30 $. Where is the 1 $??
     
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  2. mightyrick

    mightyrick Hall of Fame

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    1) Group eats. (Group=$30, Manager=$0, Waiter=$0)
    2) Group pays bill without any tip. (Group=$0, Manager=$30, Waiter=$0)
    3) Manager gives $5 rebate to group. (Group=$5, Manager=$25, Waiter=$0)
    4) Group pays a small tip ($2) to waiter. (Group=$3, Manager=$25, Waiter=$2)

    I'm not sure where the issue is.

    At the end, the group has $3. The manager has $25. The waiter has $2. $30 total for all three.
     
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  3. ScoopsHaaganDazs

    ScoopsHaaganDazs Rookie

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    10 + 10 + 10 = 30
    30 - 5 =25
    25 + 2= 27
    27 + 3 = 30
     
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  4. billnepill

    billnepill Hall of Fame

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    all in all, they each pay 9 $ and give 2 $ to the waiter =29 $ :D
     
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  5. snoflewis

    snoflewis Hall of Fame

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    the 3 people giving $2 for tip is inclusive in the $9 that they each pay.
    bill is $30, manager gives $5 back, which essentially makes the bill $25 or $8.33/person. They decide to give the waiter a $2 tip in total, which comes out to $0.67/person. so they each end up paying $9.
     
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  6. MarrratSafin

    MarrratSafin Hall of Fame

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    The way the question is laid out is misleading.
    -They pay $10 each, that's $30 total. Put it in a pool on the table.
    -The manager throw out $5, that makes $35 total in the pool.
    -They take $1 each, that means $10 + $1 = $11 each. $11 x 3 = $33.
    -Waiter takes $2.
    -$33 + $2 = $35
     
    Last edited: May 9, 2011
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  7. snoflewis

    snoflewis Hall of Fame

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    there was only $30 to begin with. when the manager gives them the money back, it comes from the $30 that was paid, so it can't be $35.
    although, if you know how to make an additional $5 appear from $30, please shoot me an email haha.
     
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  8. billnepill

    billnepill Hall of Fame

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    But they first take the one dollar each and then hand out the tip. Taking the dollar made their individual bill 9 $ already.

    From their perspective they paid 9x3 + 2 = 29.


    P.S. Your answer is correct. I tried to explain it once to a friend who never got it and said it is math failure lol...
     
    Last edited: May 9, 2011
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  9. snoflewis

    snoflewis Hall of Fame

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    haha. math never fails.
    i, on the other hand, have failed math plenty of times. lol
     
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  10. sureshs

    sureshs Bionic Poster

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    Done before on this forum
     
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  11. billnepill

    billnepill Hall of Fame

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    man you are a member in this forum for more than a half a decade :D

    Maybe non-ancient posters haven't seen it.
     
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  12. Claudius

    Claudius Professional

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    I'm just waiting for BreakPoint to say that the dollar is actually missing.
     
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  13. Legend of Borg

    Legend of Borg Legend

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    I thought this thread was about the latest controversy with Petros and his tipping habits.

    Shame.
     
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  14. MarrratSafin

    MarrratSafin Hall of Fame

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    Cool. 10 chars.
     
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  15. billnepill

    billnepill Hall of Fame

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    LMAO

    Petros already solved this problem by not giving a tip. No tip = no headaches.

    Wise man :D
     
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  16. baek57

    baek57 Professional

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    That's a pretty skimpy tip, especially after getting $5 back. $2 is barely a 6.7% tip. Generally tipping is at least 15% which would've been $4.50. They should've just left the $5 for the waitress!
     
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  17. Squall Leonheart

    Squall Leonheart Rookie

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    I believe that this is one example of why we have the order of operations: if you do math in random order, errors can occur.
     
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  18. pinky42

    pinky42 Rookie

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    No, they chipped in $27. The bill was $25 leaving $2. Instead of dividing the $2 between themselves, they gave it to the waiter. 9x3 = 25 + 2. The error is adding the $2. It is part of the $27 that is split between the bill and the tip.
     
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  19. ProgressoR

    ProgressoR Hall of Fame

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    Its stuff like this why I dropped maths at 13. I saw this puzzle back around then and could not figure it out where the missing money went. Even when i saw a so called solution, it made no sense. Maths is very dangerous, it makes money disappear and if you do not understand it its best to stay away from it. I used to stress and lose whole night's sleep about how Maths was supposed to make sense but instead it turned the world upside down.

    That is why I pay by credit card.
     
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  20. Dilettante

    Dilettante Hall of Fame

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    I have a better question:

    Where are the Enron and Lehman Bros' dollars?

    You guys with all the maths and stuff are not smart enough to answer this.
     
    Last edited: May 10, 2011
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  21. mucat

    mucat Hall of Fame

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    30

    30-5= 25

    25+3=28

    28 +2= 30
     
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