Test your math ability

This is a discussion on Test your math ability within the A Brief History of Cprogramming.com forums, part of the Community Boards category; I have one simple question for you guys to answer: Five hats are randomly distributed to the five people who ...

  1. #1
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    Test your math ability

    I have one simple question for you guys to answer:

    Five hats are randomly distributed to the five people who own them. What is the probability that all the poeple receive the correct hat?


    Good Luck

  2. #2
    Christian
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    1 in 25.

    What is the chance that was a homework queston?
    I shall call egypt the harmless dragon

    -Isaiah 30.7

  3. #3
    Just because ygfperson's Avatar
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    1/5! = 1 in 120

    a person takes a hat. s/he has a 1 in 5 chance. if the choice is correct, the next person has a 1 in 4 chance, then a 1 in 3 chance ,and so on.

    i'm sure i'm wrong... am i?

  4. #4
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    Originally posted by ygfperson
    1/5! = 1 in 120

    a person takes a hat. s/he has a 1 in 5 chance. if the choice is correct, the next person has a 1 in 4 chance, then a 1 in 3 chance ,and so on.

    i'm sure i'm wrong... am i?
    That's my answer also, I believe it to be correct.
    "...the results are undefined, and we all know what "undefined" means: it means it works during development, it works during testing, and it blows up in your most important customers' faces." --Scott Meyers

  5. #5
    Christian
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    Each person has a 1 in 5 chance of getting the correct hat. YGF your method would have worked if the queston said that No more hats would be given out once someone got the wrong hat. But everyone gets a hat no mater what.
    I shall call egypt the harmless dragon

    -Isaiah 30.7

  6. #6
    Registered User dirkduck's Avatar
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    That would just be a 5^2 one I believe...so 1 in 25 (as stated before )

  7. #7
    moi
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    1 in 3125
    hello, internet!

  8. #8
    Just because ygfperson's Avatar
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    Originally posted by Sentaku senshi
    Each person has a 1 in 5 chance of getting the correct hat. YGF your method would have worked if the queston said that No more hats would be given out once someone got the wrong hat. But everyone gets a hat no mater what.
    oh yeah... forgot about that. see what school does to you?

  9. #9
    Registered User Aran's Avatar
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    the law of permutations is in effect here.. i believe it states that (n)/((n-k)!) is the answer (where k is accepted and n are the total number of outcomes)

    [it's either (n)/((n-k)!) or (n!)/((n-k)!)]

  10. #10
    Code Goddess Prelude's Avatar
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    >Five hats are randomly distributed to the five people who own them.
    According to your wording, all five people own all five hats, so the probability is 1 in 1.

    -Prelude
    My best code is written with the delete key.

  11. #11
    darkeldar77
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    Another for 1/120

  12. #12
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    I envy the one with the red hat

  13. #13
    CIS and business major
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    1/120


  14. #14
    l'Anziano DavidP's Avatar
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    i get 1/120 also..

    I envy the one with the red hat
    hahahahaha
    My Website

    "Circular logic is good because it is."

  15. #15
    Jet_Master
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    I very much believe it is a 1 in 25 chance...
    because each hat has a chance of landing on one of five people (that is a 1 in 5 chance). but when there are five hats, the chances are multiplied by another 1 in 5 chance. therefore:
    1/5 * 1/5 = 1/25.
    therefore there is a 1 in 25 chance everyone will get the right hat...

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