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six cards with numbers 1,2,3,4,5,6 on them separately, are put in one bowl, pick out one card, put back and then pick out one card. If the sum of two cards are 8, what is the probabilities of card numbered with 5?
MY ANS:2/5
这题我也不懂呀,请指教, 我是数学白痴呀! |
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