document.write( "Question 117870: In how many ways 5 girls & 5 boys can be arranged if at least 2 girls sit together?\r
\n" ); document.write( "\n" ); document.write( "I know one method \r
\n" ); document.write( "\n" ); document.write( "10! - 5!x6!
\n" ); document.write( " but i want to it by another method so please help me for that \n" ); document.write( "
Algebra.Com's Answer #86088 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
In how many ways 5 girls & 5 boys can be arranged if at least 2 girls sit together?
\n" ); document.write( "I know one method
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\n" ); document.write( "but i want to it by another method so please help me for that
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document.write( "First we figure the number of ways that anybody can sit anywhere:\r\n" );
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document.write( "That's 10!\r\n" );
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document.write( "Now we figure the number of ways in which no two girls can sit \r\n" );
document.write( "together. These are:\r\n" );
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document.write( "1. this way, alternating seats with a boy on the far left and\r\n" );
document.write( "a girl on the far right:\r\n" );
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document.write( "B G B G B G B G B G\r\n" );
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document.write( "G B G B G B G B G B\r\n" );
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document.write( "Each of those is (5!)²\r\n" );
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document.write( "That's 2×(5!)²\r\n" );
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document.write( "2. these ways, with one pair of boys together\r\n" );
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document.write( "G (B B) G B G B G B G\r\n" );
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document.write( "G B G (B B) G B G B G\r\n" );
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document.write( "G B G B G (B B) G B G\r\n" );
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document.write( "G B G B G B G (B B) G\r\n" );
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document.write( "Each of those 4 ways are also (5!)²\r\n" );
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document.write( "So that's 4×(5!)²\r\n" );
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document.write( "So there are a total of \r\n" );
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document.write( "2×(5!)² + 4×(5!)²  ways in which no girls sit \r\n" );
document.write( "together. So we subtract 6×(5!)² from the total number of \r\n" );
document.write( "ways there are to seat anybody anywhere. The end result will\r\n" );
document.write( "count only the ways in which two or more girls sit together.\r\n" );
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document.write( "10! - 6(5!)² = 3628800 - 6(120)² = 3628800 - 6(14400) =\r\n" );
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document.write( "3628800 - 86400 = 3542400 \r\n" );
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document.write( "Edwin
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