(1)C(2,3)(2/3)²(1/3)=4/9
(2)C(2,3)(3/4)²(1/4)+C(3,3)(3/4)³=27/32
(3)C(3,3)(2/3)³×C(2,3)(3/4)²(1/4)+C(2,3)(2/3)²(1/3)×C(3,3)(3/4)³ =3/8
(1)C(2,3)(2/3)²(1/3)=4/9
(2)C(2,3)(3/4)²(1/4)+C(3,3)(3/4)³=27/32
(3)C(3,3)(2/3)³×C(2,3)(3/4)²(1/4)+C(2,3)(2/3)²(1/3)×C(3,3)(3/4)³ =3/8