document.write( "Question 271350: If you have a bag of marbles; 7 red, 5 green, and 8 blue, what's the probability of getting at least 2 red marbles in 3 draws from the bag, with replacement? Thanks...this is all new to me! \n" ); document.write( "
Algebra.Com's Answer #198691 by stanbon(75887)\"\" \"About 
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If you have a bag of marbles; 7 red, 5 green, and 8 blue, what's the probability of getting at least 2 red marbles in 3 draws from the bag, with replacement?
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\n" ); document.write( "Binomial Problem:
\n" ); document.write( "n = 3 ; p = 7/20
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\n" ); document.write( "P(2<= x <=3) = 3C2(7/20)^2(13/20) + 3C3(7/20)^3(13/20)^0
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\n" ); document.write( "= 0.2389 + 0.0429
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\n" ); document.write( "= 0.2818
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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