document.write( "Question 352388: 10 people line up for a photo, including you and your friend. How many line arrangements are there if the photographer insists on keeping 3 people in between you and your friend? \n" ); document.write( "
Algebra.Com's Answer #252130 by nyc_function(2741)\"\" \"About 
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There are 10 people: A(you), B(your friend) and 8 others.\r
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\n" ); document.write( "\n" ); document.write( "You and your friend are spaced like this:\r
\n" ); document.write( "\n" ); document.write( "A____B or B____A = two ways\r
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\n" ); document.write( "\n" ); document.write( "Select 3 of the Others and arrange them in the spaces. \r
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\n" ); document.write( "\n" ); document.write( "There are: 8P3 = 8!/5! = 336 ways.\r
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\n" ); document.write( "\n" ); document.write( "Now we have 6 \"people\" to arrange: AxyzB and 5 others.\r
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\n" ); document.write( "\n" ); document.write( "There are: 6! = 720 ways.\r
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\n" ); document.write( "\n" ); document.write( "Therefore, there are: 2 * 336 * 720 = 483,840 line arrangements.
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