document.write( "Question 252789: There are five balls that must be played in a game. Two of the balls are signed
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\n" ); document.write( "How many possible orderings (permutations) can the balls be played?\r
\n" ); document.write( "\n" ); document.write( "A) 2 B) 12 C) 60 D) 120 E) 3125
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Algebra.Com's Answer #184858 by Theo(13342)\"\" \"About 
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each signed ball have to be played in the first or last game so they are fixed at 2 games, one for each.\r
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\n" ); document.write( "\n" ); document.write( "the other 3 balls can be in games 2,3,4 in any order.\r
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\n" ); document.write( "\n" ); document.write( "all balls can be played in one game only.\r
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\n" ); document.write( "\n" ); document.write( "the number of permutations for the 3 unsigned balls is 3! = 3*2*1 = 6.\r
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\n" ); document.write( "\n" ); document.write( "the two signed balls can be played in the first or last position only.\r
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\n" ); document.write( "\n" ); document.write( "the number of permutations for the signed balls is 2!.\r
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\n" ); document.write( "\n" ); document.write( "the total order of permutations is 2 * 6 = 12.\r
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\n" ); document.write( "\n" ); document.write( "that's 2 permutations for the signed balls times 6 permutations for the unsigned balls.\r
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\n" ); document.write( "\n" ); document.write( "here's how it works.\r
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\n" ); document.write( "\n" ); document.write( "let a,e be the signed balls.
\n" ); document.write( "let b,c,d be the unsigned balls.\r
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\n" ); document.write( "\n" ); document.write( "your possible permutations for games 1,2,3,4,5 are:\r
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\n" ); document.write( "\n" ); document.write( "a,b,c,d,e
\n" ); document.write( "a,b,d,c,e
\n" ); document.write( "a,c,b,d,e
\n" ); document.write( "a,c,d,b,e
\n" ); document.write( "a,d,b,c,e
\n" ); document.write( "a,d,c,b,e\r
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\n" ); document.write( "\n" ); document.write( "e,b,c,d,a
\n" ); document.write( "e,b,d,c,a
\n" ); document.write( "e,c,b,d,a
\n" ); document.write( "e,c,d,b,a
\n" ); document.write( "e,d,b,c,a
\n" ); document.write( "e,d,c,b,a\r
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