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Math Help - Probability Puzzle

  1. #1
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    Probability Puzzle

    There are 50 red and 50 blue balls. Arrange them in 2 baskets, such that the probability of getting a blue ball is more.

    Please help.
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  2. #2
    Grand Panjandrum
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    Quote Originally Posted by kens View Post
    There are 50 red and 50 blue balls. Arrange them in 2 baskets, such that the probability of getting a blue ball is more.

    Please help.
    I think I need more detail for this

    RonL
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  3. #3
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    There are two baskets and we can put any number(even zero) balls in each of them.

    I guess we can assume that x blue balls should be put in the first basket which has a total of n balls.
    Then, we maximize
    x/n +(50-x)/(100-n).

    Is this correct? What is the answer?
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  4. #4
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    Hello, kens!

    There are 50 red and 50 blue balls.
    Arrange them in 2 baskets, such that the probability of getting a blue ball is a maximum.

    This is a classic problem/puzzle/riddle.

    I'll hide the answer.
    Drag your cursor over the region between the asterisks.

    * Place one blue ball in one basket, the rest in the other basket.

    The probability of getting a blue ball from Basket #1 is: 1

    The probability of getting a blue ball from Basker #2 is: 49/99


    P(Basket 1 and blue) = (1/2)(1) = 1/2

    P(Basket 2 and blue) = (1/2)(49/99) = 49/198


    Therefore: P(blue) = 1/2 + 49/198 = 148/198 ≈ 75%
    *

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  5. #5
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    Thanks. Can you please suggest some books for such puzzles?
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