(3)取出四顆中數字是 2 的倍數恰有一顆，是 3 的倍數也恰有一顆，且是 5的倍數也恰有一顆。例如(6,13,19,25)

Question 2. [Maximum mark: 6] Jack and John have decided to play a game. One roll of a die is considered as one round of the game. On each round, John agrees to pay Jack $4 if 1 or 2 is rolled, Jack agrees to pay John $2 if 3, 4, 5 or 6 is rolled, and who is paid wins the round. In the end, who earns money wins the game. Now Jack and John roll a die 12 times. Let A denote the number of rounds Jack wins. Find the expected value of A, E[A]= __________.

(3)取出四顆中數字是 2 的倍數恰有一顆，是 3 的倍數也恰有一顆，且是 5的倍數也恰有一顆。例如(6,13,19,25)

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