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Unlikely evets and probability

  1. May 17, 2010 #1
    I was thinking about unlikely evenst and conclude they must happen all the time. Imagine I draw a card from a deck, the odds for a particular card to come out= 1/52. Now I replace, shuffle and draw another card, the odds of the sequence of two card are =1/52*1/52 so and we can keep multiplying this by 1/52 for each card if we repeat the process:
    2 card = 1/2704
    3 cards =140,068
    4 cards = 7,311,616
    5 cards 380,204,032
    6 cards =19.77 billion to one.
    7 cards = 1.028 trillion to one.

    Now presumably casinos are dealing thousands of cards down every day, (Maybe millions?) and so the odds of any particualr sequence of cards being dealt is utterly astronimical. So one cannot sy an event cannot happen becuase its unlikely, it has to be more unliekly than any other event. Anyone disagree with this maths?
  2. jcsd
  3. May 18, 2010 #2
    I don't disagree with the math, perhaps your argument isn't cogent though.
  4. May 18, 2010 #3
    If your aim was to disprove the notion that unlikely events can't happen, you've succeeded.
  5. May 20, 2010 #4
    If you could predict the future with 100% accuracy, there wouldn't be any unlikely events. There would only be certain events and impossible events.

    EDIT: More precisely, certain or impossible outcomes for a given trial.
    Last edited: May 21, 2010
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