解按乘法公式有 P{951=0,52=0} P(1=0}P(2=0|5=0}=×=0.1 23 P151=0,2=1}=×n=0.3 32 P{51=1,92=0}=x×=0.3 32 P151=1,52=1}=× 4 0.39 解 按乘法公式有 0.3 4 2 5 3 { 1, 1} 0.3 4 2 5 3 { 1, 0} 0.3 4 3 5 2 { 0, 1} 0.1 4 1 5 2 { 0} { 0 | 0} { 0, 0} 1 2 1 2 1 2 1 2 1 1 2 = = =  = = = =  = = = =  = = = = =  = = = = x x x x x x x x x x x P P P P P P