document.write( "Question 847615: I'm a bit confused on exactly what these are asking me. I am posting the question along with where I am in the answer. I don't know if I'm way off base here. \r
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\n" ); document.write( "\n" ); document.write( "You have a bag of 500 marbles. You were told by the clerk when you got the bag that they are 99% green and 1% red. If you pull out 5 marbles at random and they are 4 red and 1 green, what does that tell you? \r
\n" ); document.write( "\n" ); document.write( "First I am looking at the probability of pulling out a red marble in the first random draw. If the clerk was correct then out of 500 marbles exactly 5 should be red. I then used the combination rule since the marbles are all distinct and each marble without replacement is selected at random. I found 255,244,687,600 possible combinations of marble selection. The clerk is incorrect because it is unlikely 80% of the red marbles would be pulled out in the first draw.
\n" ); document.write( "(If I am way off base here, please steer me back). \r
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Algebra.Com's Answer #510580 by richwmiller(17219) $\"\"$ $\"About$

You can put this solution on YOUR website!
Probability doesn't tell us what will happen next. \r
\n" ); document.write( "\n" ); document.write( "Yes it is unlikely to pick 4 red marbles when there are only 5. However it is still possible.
\n" ); document.write( "What does that tell you? Don't depend on the odds in one instance. Over the long run, you SHOULD make out ok.
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