即玩家交錢的概率是9/14;
2.同樣,“320”的概率是:(C3/3 * C2/3 * P3/3)/(C5/9)= 18/126 = 1/7;“311”的概率為:(C3/3 * c 1/3 * c 1/3)/(C5/9)= 27/126 = 3。
利潤的期望是:9/14 * 5-3/14 * 2-1/7 * 10 = 19/14。