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Math Help - Need some help determining if there is more I have to do with this question

  1. #1
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    Need some help determining if there is more I have to do with this question

    "A bag contains 3 red balls, 4 yellow balls, and 5 white balls. If two balls are being drawn from the bag without replacement, what is the probability that the first ball is yellow and the second ball is white?"

    So I know that to calculate the probability of drawing two balls you calculate the individual probability of drawing each ball then multiply them together. But do I need to do any additional calculations for the probability that they are drawn in the correct order (first is red, second is white)? If so, what equation would I use to do that? Or am I over-thinking this?
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  2. #2
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    Re: Need some help determining if there is more I have to do with this question

    Quote Originally Posted by DEADTERMINATOR View Post
    "A bag contains 3 red balls, 4 yellow balls, and 5 white balls. If two balls are being drawn from the bag without replacement, what is the probability that the first ball is yellow and the second ball is white?"
    The answer is \frac{?}{?}\cdot\frac{5}{11}.
    Now you fill in ??
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  3. #3
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    Re: Need some help determining if there is more I have to do with this question

    No, that's all you need to do. Initially there are 3 red balls, 4 yellow balls, and 5 white balls for a total of 12 balls. The probability of drawing a yellow ball is 4/12= 1/3. Once that is done, there are 3 red balls, 3 yellow balls, and 5 balls for a total of 11 balls. The probability of drawing a white ball is 5/11. Yes, multiply them together.
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