小学生两百字作文大全:甲乙两人投篮,投总的概率分别是0.6,0.7,今各投3次,则两人投中相等的概率为()

来源:百度文库 编辑:杭州交通信息网 时间:2024/04/27 17:19:45

甲:0中概率 0.4*0.4*0.4 =0.064
1中概率 0.4*0.6*0.4*3=0.288
2中概率 0.4*0.6*0.6*3=0.432
3中概率 0.6*0.6*0.6 =0.216
乙:0中概率 0.3*0.3*0.3 =0.027
1中概率 0.7*0.3*0.3*3=0.189
2中概率 0.7*0.7*0.3*3=0.441
3中概率 0.7*0.7*0.7 =0.343

故两人投中相等的概率是:
0.064*0.027+0.288*0.189+0.432*0.441+0.216*0.343=0.001728+0.054432+0.074088=
0.130248

可能是发挥好吧`心态很重要的阿