请教一道数学概率计算题 请教一道概率计算题
\u8bf7\u6559\u4e00\u4e2a\u6570\u5b66\u6982\u7387\u7684\u9898\u76ee\u53ef\u4fe1\u662f\u5168\u90e8\u8bf4\u771f\u8bdd\u6216\u90e8\u5206\u4eba\u8bf4\u771f\u8bdd\u3002\u8ba1\u7b97\u8d77\u6765\u6bd4\u8f83\u590d\u6742\u3002\u6240\u4ee5\u4ece\u53cd\u9762\u8ba1\u7b97\u3002\u6240\u6709\u4eba\u540c\u65f6\u8bf4\u8c0e\u5373\u4e3a\u4e0d\u53ef\u4fe1\u3002
1\u300180%
2\u30011-20% \u00d7 50%=90%
\u7532\u8bf4\u8c0e \u4e59\u8bf4\u8c0e
3\u30011-20% \u00d7 50% \u00d7 10%=99%
\u7532\u8bf4\u8c0e \u4e59\u8bf4\u8c0e \u4e19\u8bf4\u8c0e
4\u30011-20% \u00d7 50% \u00d7 10% \u00d7 90%=99.1%
\u7532\u8bf4\u8c0e \u4e59\u8bf4\u8c0e \u4e19\u8bf4\u8c0e \u4e01\u8bf4\u8c0e
\u6c42\u91c7\u7eb3~~~~
\u5c065\u4e2a\u4eba\u5206\u62103\u7ec4\uff0c\u6bcf\u7ec4\u81f3\u5c11\u4e00\u4e2a\u4eba\uff0c\u53ea\u67092\u79cd\u5206\u6cd5\uff1a1+1+3\u62161+2+2
\u7b2c\u4e00\u79cd\u60c5\u51b5\u5171\u6709\uff1aC\uff085\uff0c3\uff09=10
\u7b2c\u4e8c\u79cd\u60c5\u51b5\u5171\u6709\uff1aC\uff085\uff0c2\uff09*C\uff083,2\uff09/A\uff082,2\uff09=15
\u6240\u6709\u7b26\u5408\u6761\u4ef6\u60c5\u51b5\u603b\u548c=\uff0810+15\uff09*A\uff083,3\uff09=150
\u57fa\u672c\u4e8b\u4ef6\u603b\u6570=3^5=243
\u6240\u4ee5\u6982\u7387=150/243=50/81
来自乙的产品有5a件,其中次品为5a*0.30=1.5a件
则抽的一件次品来自甲的概率为
4.75a/(4.75a+1.5a)=76%
分两步,来自甲厂的概率为95%,是次品的概率是(1-95%):
95%*5%
满意请给最佳!不懂请追问!谢谢!
...假设我们总共有10000个产品,甲的有9500,乙的500,甲中次品有495,乙中有150个,因为是次品已知,所以概率为495除以(495加150)约等于0.7674418,就等于答案~~~少年你可否知晓~~~
设一共生产了1个,0.95*0.05+0.05*0.3是次品甲厂0.95*0.05所以0.95*0.05/0.95*0.05+0.05*0.3是来自甲厂的概率
来自甲厂的概率为95%,是次品的概率是(1-95%):95%*5%
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