作者wimiu0311

您犯了點小錯
正解算式：
P=1-(C(10,7)+C(10,6)*C(4,1)*C(3,1)+C(10,5)*C(5,2)*C(3,2))/(C(10,7)*C(10,7))
=1-(120+2520+7560)/14400
=1-17/24=7/24