there are 4 white balls, 2 red balls and 1 yellow ball in a bag. two balls are drown from the bag with replacement.find the probability of:
i)at lease 1 red ball
Please show the clear step=]
f.3 probability
2011-01-08 1:05 am
回答 (2)
2011-01-08 1:50 am
✔ 最佳答案
i)P(At least 1 red ball)
= 1 - P(No red ball)
= 1 - P(white or yellow 2 times with replacement)
= 1 - [(4+1)/(4+2+1)] [(4+1)/(4+2+1)]
= 1 - (5/7)(5/7)
= 24/49
2011-01-08 2:25 am
there are 4 white balls, 2 red balls and 1 yellow ball in a bag. two balls are drown from the bag with replacement.find the probability of:
i)at lease 1 red ball
_________________________________________
P(at least 1 red ball)
(2/7)(4/7)(2)+(2/7)(2/7)+(2/7)(1/7)(2)
(16/49)+(4/49)+(4/49)
24/49
i)at lease 1 red ball
_________________________________________
P(at least 1 red ball)
(2/7)(4/7)(2)+(2/7)(2/7)+(2/7)(1/7)(2)
(16/49)+(4/49)+(4/49)
24/49
收錄日期: 2021-04-21 22:18:26
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20110107000051KK00695