document.write( "Question 1138507: If you are dealt 3 cards from a shuffled deck of 52 cards, find the probability of getting one queen and two kings. \n" ); document.write( "
Algebra.Com's Answer #756422 by Theo(13342)\"\" \"About 
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i believe it will be 4c2 * 4c1 / 52c3.\r
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\n" ); document.write( "\n" ); document.write( "that's the number of ways you can get 2 kings from 4 kings times the number of ways you can get 1 queen out of 4 queens divided by the number of ways you can get any 3 cards out of 52 cards.\r
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\n" ); document.write( "\n" ); document.write( "4c3 = 4! / (2! * 2!) = 6
\n" ); document.write( "4c1 = 4! / (1! * 3!) = 4
\n" ); document.write( "52c3 = 52! / (3! * 49!) = 22100\r
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\n" ); document.write( "\n" ); document.write( "the probability is therefore 24 / 22100 = .0010859729.\r
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\n" ); document.write( "\n" ); document.write( "you can do it another way.\r
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\n" ); document.write( "\n" ); document.write( "to get 2 kings and one queen out of deck of 52 cards give you 3 possibilities.\r
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\n" ); document.write( "\n" ); document.write( "they are KKQ, KQK, and QKK.\r
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\n" ); document.write( "\n" ); document.write( "that is draws 1, 2 and 3 in that order.\r
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\n" ); document.write( "\n" ); document.write( "you can draw a king on the first draw and a king on the second draw and a queen on the third draw, or you can draw a kind on the first draw and a queen on the second draw and a king on the third draw, or you can draw a queen on the first draw and a king on the second draw and a king on the third draw.\r
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\n" ); document.write( "\n" ); document.write( "this is all without replacement, so the probability changes each draw.\r
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\n" ); document.write( "\n" ); document.write( "for KKQ, the probaiblity is 4/52 * 3/51 * 4/50.
\n" ); document.write( "for KQK, the probability is 4/52 * 4/51 * 3/50.
\n" ); document.write( "for QKK, the probability is 4/52 * 4/51 * 3/50.\r
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\n" ); document.write( "\n" ); document.write( "each oone of these probabilties is the same, so the total probability would be 3 * (4 * 3 * 4) / (52 * 51 * 50) = = .0010859729, the same as we got using the other method.\r
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\n" ); document.write( "\n" ); document.write( "i believe that's your answer.\r
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\n" ); document.write( "\n" ); document.write( "note that ncx is equal to n! / (x! * (n-x)!).\r
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\n" ); document.write( "\n" ); document.write( "when n = 4 and x = 2, that becomes 4! / (2! * 2!).\r
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\n" ); document.write( "\n" ); document.write( "when n = 4 and x = 1, that becomes 4! / (1! * 3!).\r
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\n" ); document.write( "\n" ); document.write( "when n = 52 and x = 3, that becomes 52! / (3! * 49!).\r
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\n" ); document.write( "\n" ); document.write( "ncx can also be written as c(n,x).\r
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\n" ); document.write( "\n" ); document.write( "they mean the same thing.
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