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  1. #1
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    At least 1.

    Hello
    I'm trying to understand an example given in a book I have. The book is The Theory of Gambling and Statistical Logic, R Epstein, page 16.

    "The probability of drawing at least one king in two tries from a deck of 52 cards is 396/(52*51) = 0.149 ."

    I know I can solve this question by finding the probability of no king and subtracting from one.
    1 - (48/52 * 47/51) = 0.149

    In the first example I don't understand where 396 comes from. If I was working from the beginning , how would I get to 396?

    phil
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  2. #2
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    Quote Originally Posted by phil_b View Post
    Hello
    I'm trying to understand an example given in a book I have. The book is The Theory of Gambling and Statistical Logic, R Epstein, page 16.

    "The probability of drawing at least one king in two tries from a deck of 52 cards is 396/(52*51) = 0.149 ."

    I know I can solve this question by finding the probability of no king and subtracting from one.
    1 - (48/52 * 47/51) = 0.149

    In the first example I don't understand where 396 comes from. If I was working from the beginning , how would I get to 396?

    phil
    Draw a tree diagram. Then you will understand where the following comes from:

    (4)(3) + (4)(48) + (48)(4) = 396.
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  3. #3
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    Thank you Mr fantastic.
    I must start using tree diagrams more.
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