document.write( "Question 842435: Four men and eight women are to line up for a picture with the four men in the middle. How many ways can this be done? (Assume there are four women on each side of the group of men) \n" ); document.write( "
Algebra.Com's Answer #507582 by Theo(13342)\"\" \"About 
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the 4 men in the middle can be arranged 4! ways.
\n" ); document.write( "the 8 women all in a row can be arranged in 8! ways.
\n" ); document.write( "the total number of ways will be 4! * 8! = 967,680 ways
\n" ); document.write( "you take the 8 women in a row and split them in half and stick the 4 men in the middle.
\n" ); document.write( "4! is equal to 24
\n" ); document.write( "8! is equal to 40320.
\n" ); document.write( "for each of the 40320 arrangements of the women, you can stick 24 arrangements of the men in the middle.
\n" ); document.write( "this makes the total number of arrangements equal to 24 * 40320 which is equal to 967680.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "let's assume smaller numbers so you can see what's happening.
\n" ); document.write( "assume 2 men and 4 women.
\n" ); document.write( "the men can be arranged in 2! ways which is equal to 2.
\n" ); document.write( "the women can be arranged in 4! ways which is equal to 24.
\n" ); document.write( "the total ways they can be arranged is 2 * 24 = 48.
\n" ); document.write( "let letters represent the men and let number represent the women.
\n" ); document.write( "the letters will be a and b.
\n" ); document.write( "the numbers will be 1 and 2 and 3 and 4.
\n" ); document.write( "the men can be arranged as:
\n" ); document.write( "ab
\n" ); document.write( "ba
\n" ); document.write( "the women can be arranged as:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "1234
\n" ); document.write( "1243
\n" ); document.write( "1324
\n" ); document.write( "1342
\n" ); document.write( "1423
\n" ); document.write( "1432
\n" ); document.write( "2134
\n" ); document.write( "2143
\n" ); document.write( "2314
\n" ); document.write( "2341
\n" ); document.write( "2413
\n" ); document.write( "2431
\n" ); document.write( "3124
\n" ); document.write( "3142
\n" ); document.write( "3214
\n" ); document.write( "3241
\n" ); document.write( "3412
\n" ); document.write( "3421
\n" ); document.write( "4123
\n" ); document.write( "4132
\n" ); document.write( "4213
\n" ); document.write( "4231
\n" ); document.write( "4312
\n" ); document.write( "4321\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "all you do now is split the 4 women down the middle and stick the 2 men in between.
\n" ); document.write( "each of the 24 arrangements for the women will contain 2 arrangements for the men, so you will wind up with 2 * 24 = 48 total arrangements.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "I'll show you what happens with the first arrangement of the women.\r
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\n" ); document.write( "\n" ); document.write( "the first arrangement is:\r
\n" ); document.write( "\n" ); document.write( "1234\r
\n" ); document.write( "\n" ); document.write( "the 2 arrangements for the men are ab and ba\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "stick the 2 men in the middle and you get:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "12 ab 34
\n" ); document.write( "12 ba 34\r
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\n" ); document.write( "\n" ); document.write( "this happens with all 24 arrangements of the women, so the total number of arrangements becomes 48.\r
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