document.write( "Question 1070372: 5 girls and 4 boys sit in a row. If only two boys sit next to each other , find the number of
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Algebra.Com's Answer #685675 by Edwin McCravy(20055)\"\" \"About 
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document.write( "We line up the 5 girls in 5!=120 ways.  \r\n" );
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document.write( "_G_G_G_G_G_\r\n" );
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document.write( "Next we will insert the boys among the girls. There are 6 insertion\r\n" );
document.write( "places to choose for the boys to be inserted, indicated above by \"_\"'s.\r\n" );
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document.write( "We choose two boys to sit together left to right in 4*3 = 12 ways.\r\n" );
document.write( "We choose an insertion place for that pair of boys any of 6 ways.\r\n" );
document.write( "We choose a different insertion place for the older of the two \r\n" );
document.write( "remaining boys any of 5 ways.\r\n" );
document.write( "We choose another different insertion place for the one remaining boy \r\n" );
document.write( "any of 4 ways.\r\n" );
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document.write( "Answer: (120)(12)(6)(5)(4) = 172800 ways.\r\n" );
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document.write( "Edwin
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