1. The probabilities of solving a problem by 3 students are 0.6, 0.4 and 0.7 respectively. What is the probability that
a) at least one of them solve the problem?
b) exactly one of them solve the problem?
2. Three dices are thrown, what is the probability that
a) there is no '6'?
b) there is at least one '6'?
F5 Probability
2011-05-18 5:32 am
回答 (1)
2011-05-18 5:41 am
✔ 最佳答案
1(a)P(at least one of them solve the problem)
= 1 - (1 - 0.6)(1 - 0.4)(1 - 0.7)
= 1 - 0.4*0.6*0.3
= 1 - 0.072
= 0.928
(b) P(exactly one of them solve the problem)
= 0.6(1 - 0.4)(1 - 0.7) + (1 - 0.6)0.4(1 - 0.7) + (1 - 0.6)(1 - 0.4)0.7
= 0.324
2(a) P(there is no '6')
= (5/6)^3
= 125/216
(b) P(there is at least one '6')
= 1 - 125/216
= 91/216
收錄日期: 2021-04-26 14:55:08
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20110517000051KK01162