document.write( "Question 981351: A class has 21 students. Eight of the students are boys and thirteen are girls.
\n" ); document.write( "Five students are asked to come to the board.\r
\n" ); document.write( "\n" ); document.write( "In how many ways can the five students be selected to come to the board, where
\n" ); document.write( "the order of the students does not matter, but at least two of the students are
\n" ); document.write( "girls? \n" ); document.write( "

Algebra.Com's Answer #602480 by Edwin McCravy(20056) $\"\"$ $\"About$

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A class has 21 students. Eight of the students are boys and thirteen are girls.
\n" ); document.write( "Five students are asked to come to the board.\r
\n" ); document.write( "\n" ); document.write( "In how many ways can the five students be selected to come to the board, where
\n" ); document.write( "the order of the students does not matter, but at least two of the students are
\n" ); document.write( "girls?
\n" ); document.write( "

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document.write( "First we calculate the number of ways any 5 of the 21 students could come\r\n" );
document.write( "to the board regardless of their sex.\r\n" );
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document.write( "That's 21C5 = 20349 ways\r\n" );
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document.write( "From that we must calculate and subtract:\r\n" );
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document.write( "1. The number of ways 5 boys and 0 girls can come to the board.\r\n" );
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document.write( "That's 8C5 = 56 ways\r\n" );
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document.write( "2. The number of ways 4 boys and 1 girl can come to the board. \r\n" );
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document.write( "We select the girl 13 ways, and the 4 boys 8C4 = 70 ways.\r\n" );
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document.write( "Thats (13)(70) = 910 ways\r\n" );
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document.write( "Answer 20349 - 56 - 910 = 19383 ways\r\n" );
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document.write( "Edwin

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