有1,2,3,4支籤, 取後不回, 問第二支籤後與第一支兩支籤數字相加為奇數機率？ 請附詳解謝謝！?
回答 (2)
2017-11-13 11:34 pm
相加為奇數=1+2, 1+4, 3+2, 3+4 共4個
不限=C(4,2)=4!/(4-2)!2!=6個
相加為奇數機率=4/6
不限=C(4,2)=4!/(4-2)!2!=6個
相加為奇數機率=4/6
2017-11-13 8:21 pm
只有1次奇才形成[相加為奇]
P(1st 奇)*P(2nd 偶)+P(1st 偶)*P(2nd 奇)
=(1/2)*(2/3)+(1/2)*(2/3)
Hope I am right and you understand.
P(1st 奇)*P(2nd 偶)+P(1st 偶)*P(2nd 奇)
=(1/2)*(2/3)+(1/2)*(2/3)
Hope I am right and you understand.
收錄日期: 2021-05-01 15:49:32
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20171113121405AAuhEuL