Question

盒中有5个红球,3个白球,2个黑球, 任取3个球，恰好取到一红一白一黑的概率为

Answer 1

取法总数是10个里取3个的组合C(10,3)=10*9*8/6=120
恰好取到一红一白一黑是C(5,1)C(3,1)C(2,1)=5*3*2=30
所以概率为C(5,1)C(3,1)C(2,1)/C(10,3)=30/120=0.25

Answer 2

取法总数是10个里取3个的组合C(10,3)=10*9*8/6=120
恰好取到一红一白一黑是C(5,1)C(3,1)C(2,1)=5*3*2=30
所以概率为C(5,1)C(3,1)C(2,1)/C(10,3)=30/120=0.25

Answer 3

p=C(5,1)C(3,1)C(2,1)/C(10,3)=30/120=0.25