Re: This problem is pissing me off
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An urn contains 5 red balls, 3 white balls, and 6 blue balls. Determine the probability that they are drawn in the order of blue, white, and red, given that each ball is NOT replaced in the urn after it is drawn.
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6/14 * 3/13 * 5/12 = 15/364
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yeah, thats what I get. They come up with a different answer (14/2184). I didn't think I could be wrong cuz its such a simple problem. Its also not the first problem that their answer has been different from mine either, and the fact they don't show the solutions to all the problems is insanely stupid. This things going in the trash. Thanks for making me not feel like a ginormous retard, heh.
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It's clearly a mistake on the CD. Also, they should've shown the solutions to all problems. The correct answer is 15/364, as you've determined:
6/14 * 3/13 * 5/12 = 90/2184 = 15/364
The mistake that the author of the problem made is that the denominators were correctly multiplied, but the numerators were added, producing an answer of 14/2184. Even a mathematician or statistician can make a simple mistake.
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