Probability Question...

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Probability Question...

by r_walid » Sun Oct 11, 2009 12:56 pm
If there are 6 blue balls and 4 red balls in a bucket. what is the probability that if i am to draw twice that i get 2 blue balls? please explain your reasoning.

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by dmateer25 » Sun Oct 11, 2009 1:43 pm
If there is no replacement of the balls then it would be:

6/10 * 5/9 = 30/90 = 1/3

There are 6 blue balls, so there is a 6 out of 10 chance of choosing a blue ball first. After you choose the first blue ball, there are 5 blue balls lefts. Thus, there is a 5 out of 9 chance of choosing a blue ball second. Multiply the two and you get 1/3

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by mjsobo » Sun Oct 11, 2009 8:22 pm
if there is replacement, then the answer is simply:
6/10*6/10=.36
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