document.write( "Question 852708: 7 boys and 6 girls sit in a row. What is the probability of having a
\n" ); document.write( "boy at each end \n" ); document.write( "

Algebra.Com's Answer #514141 by Edwin McCravy(20056) $\"\"$ $\"About$

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document.write( "Let these 13 blanks represents the seats:\r\n" );
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document.write( "_ _ _ _ _ _ _ _ _ _ _ _ _\r\n" );
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document.write( "We calculate the number of ways this can happen,\r\n" );
document.write( "with the other 11 people seated between the boys. \r\n" );
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document.write( "B _ _ _ _ _ _ _ _ _ _ _ B\r\n" );
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document.write( "and then we'll divide by 13!, the number of ways \r\n" );
document.write( "anybody can sit anywhere.\r\n" );
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document.write( "For \r\n" );
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document.write( "B _ _ _ _ _ _ _ _ _ _ _ B\r\n" );
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document.write( "we choose the boy on the left in 7 ways and the boy on the right\r\n" );
document.write( "in 6 ways, and the 11 remaining people in the middle in 11! ways.\r\n" );
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document.write( "So that's 7󬝭1! successful ways, with boys on each end.\r\n" );
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document.write( "Now we'll divide that by 13!\r\n" );
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document.write( "Edwin

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