document.write( "Question 876801: There are 6 children and husband/wife have to be in the middle. How many ways can they be seated? \n" ); document.write( "
Algebra.Com's Answer #529016 by jim_thompson5910(35256)\"\" \"About 
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Let's say we have these 8 people: A,B,C,D,E,F,G,H\r
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\n" ); document.write( "\n" ); document.write( "Let A and B be the husband and wife. Consider them as one person. Call this \"person\" Z\r
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\n" ); document.write( "\n" ); document.write( "So we now have this group Z,C,D,E,F,G,H\r
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\n" ); document.write( "\n" ); document.write( "\"Person\" Z has to be in the middle, so let's force Z to be in slot 4 to get C,D,E,Z,F,G,H\r
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\n" ); document.write( "\n" ); document.write( "Z is locked in slot 4 and cannot move. There are 7-1 = 6 other slots. So there are 6! = 6*5*4*3*2*1 = 720 ways to arrange them.\r
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\n" ); document.write( "\n" ); document.write( "Because we can arrange the husband and wife to be on either side of each other (to have AB or BA) we need to double 720 to get 2*720 = 1,440\r
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\n" ); document.write( "\n" ); document.write( "So there are 1,440 ways to seat this group of 8 people.\r
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