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One of these is wrong.

  1. May 13, 2015 #1

    julian

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    I buy a box of 28 doughnuts with the intention of eating two doughnuts each lunch time. If I stick to two doughnuts per day I end up eating the last two doughnuts on say a Thursday. (I then need to start the next box of 28 doughnuts the day after that on the Friday at lunch time.)

    I have a question about the first box of 28 doughnuts...

    QUESTION: If on some of the lunch times I eat 3 doughnuts instead of 2 (so I eat an extra doughnut), how many extra doughnuts would I have eaten in order to have none left to eat on the Wednesday?

    Here are two different answers:

    ANSWER A: If I don't have the two doughnuts I was going to eat on the Thursday and if I don't
    have the two I was going to eat on the Wednesday, I must have eaten FOUR extra
    doughnuts.

    ANSWER B: I would have to start the second box of doughnuts on the Wednesday instead of
    starting it on the Friday. Wednesday lunch time is 3 days earlier than Friday lunch time because we can count Wednesday 1, Thursday 2, Friday 3. Therefore I must have eaten 3 day's worth extra or in other words SIX extra doughnuts.

    Which answer is correct?
     
    Last edited: May 13, 2015
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  3. May 13, 2015 #2

    PeroK

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    If Wednesday is 3 days earlier than Friday, then Thursday is 2 days earlier than Friday, then Friday is a day earlier than Friday, and, I guess, Saturday is then the same day as Friday?
     
  4. May 13, 2015 #3

    julian

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    Are you saying ANSWER B is absurd?
     
  5. May 13, 2015 #4

    PeroK

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    Yes, it's absurd!
     
  6. May 13, 2015 #5

    julian

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    Hi PeroK. Is ANSWER A O.K.?
     
  7. May 13, 2015 #6
    By your definition of counting days, Each day is 1 day earlier than the day itself. So we have a problem with B.
    E: oh nvm, PeroK already mentioned this, I was just reading the first post.
     
  8. May 13, 2015 #7

    PeroK

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    Yes, it's got to be 4.
     
  9. May 13, 2015 #8

    DaveC426913

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    Another way of saying the same thing:

    No you can't. Wednesday beginning-of-lunch (say, 12PM) to Friday beginning-of-lunch (12PM) is 2 days, not 3.

    What you're trying to do is count Wednesday 12PM to Friday 1PM.
     
  10. May 13, 2015 #9

    BobG

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    A is correct, but it's also irrelevant. Those doughnuts will be stale by the first Monday.
     
  11. May 13, 2015 #10
    Since you got an answer let's talk about eating doughnuts every day for lunch... please tell me no one actually does that. You may as well be eating candy.
     
  12. May 14, 2015 #11

    julian

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    I just came up with doughnuts for the purposes of the question.
     
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