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#1 2007-06-13 23:13:02
- MickD
- Member
- Registered: 2007-06-13
- Posts: 2
Probability
Can someone please help with this poser
A bag containing 1 green, 1 red and 5 white balls. If I pull 1 ball without replacing it, then pull out another.
What is the probabilty that I have pulled out the red and green ball
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#2 2007-06-13 23:48:47
- JaneFairfax
- Member
- Registered: 2007-02-23
- Posts: 6,868
Re: Probability
The probability that you pull out the red ball first is
. The probability that you then pull out the green ball is . Hence the probability that you pull out the red ball followed by the green ball is .The probability that you take out the green ball first and then the red ball is the same.
Hence the probability of withdrawing the red and green balls is
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