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  • a)How many cards must be selected from a standard deck of 52 cards to guarantee that at least three cards of the same su

    a)How many cards must be selected from a standard deck of 52 cards to guarantee that at least three cards of the same suit are chosen?
    b)How many must be selected to guarantee that at least three hearts are selected?
    英語人氣:231 ℃時間:2020-06-04 20:16:02
    優(yōu)質解答
    抽屜原理及最差原則
    建立抽屜,4種花色看做4個抽屜,考慮最差情況:
    (1)前8張,每種花色各兩張
    那么再抽出任意一張,前面8張中肯定與這張花色相同
    即至少要抽出8+1=9張
    (2)黑桃占13張,紅桃占13張,其余的占26張,所以至少要取26+3=29張
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