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Homework Help: Drawing cards probability

  1. Dec 14, 2007 #1
    Drawing cards:
    Two cards are drawn from a 52 card deck. What is the probability that
    A. 1 card is black and 1 card is red
    B. Both cards are the same color
    C. Both cards are red?

    Please I need help
    Thank youu
  2. jcsd
  3. Dec 14, 2007 #2


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    Let's start easy: Suppose I draw just one, what is the chance that it is black?
    Now, I have a deck with 51 cards, of which 26 are red and 25 black. I draw one, what is the chance that it is red? Now what is the chance that both happen in sequence?
    Now do the same for the case where the red one is drawn first, and add the probabilities.
  4. Dec 14, 2007 #3


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  5. Dec 14, 2007 #4


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    Dearly Missed

    I have never understood much about probability; could you please offer me some clues, for example by posting what you have done so far?

    You shouldn't expect people to manage this without your cooperative help! :smile:
  6. Dec 14, 2007 #5
    As CompuChip suggested, try the above method and post what you get. You might also want to familiarize and brush up on combinatorics. If you know how to calculate permutation and combination, it should be good, at least for now. This makes your job "slightly" easier in the above problem, and very easy in problems like, choosing four cards from 52 each of different suite. In that case, it can take a while to calculate the various ways of suite selection (i.e. first hearts, then spades etc. and also other combinations).

    But if your combinatorics is good, then you can directly use those concepts in calculating Probability, that makes your life easier.

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