document.write( "Question 841542: Combinations
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Algebra.Com's Answer #506991 by Edwin McCravy(20055)\"\" \"About 
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In how many ways can a group of 10 people be divided into (a) two groups consisting of 7 and 3 people
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document.write( "(10 choose 3) AND THEN (7 choose 7)\r\n" );
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document.write( "C(10,3)·C(7.7) = 120·1 = 120\r\n" );
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document.write( "Notice that it doesn't matter if you choose the 7 people first:\r\n" );
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document.write( "(10 choose 7) AND THEN (3 choose 3)\r\n" );
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document.write( "C(10,7)·C(3,3) = 120·1 = 120\r\n" );
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\n" ); document.write( "3. In how many ways can a group of 10 people be divided into (b) three groups consisting of 4,3 and 2 people?
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document.write( "(This means that 1 person is not chosen)\r\n" );
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document.write( "(10 choose 4) AND THEN (6 choose 3) AND THEN (3 choose 2)\r\n" );
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document.write( "C(10,4)·C(6,3)·C(3,2) = 210·20·3 = 12600\r\n" );
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document.write( "Notice that it doesn't matter which order you choose the groups,\r\n" );
document.write( "The numbers to multiply are different but he answer is theame\r\n" );
document.write( "in every case\r\n" );
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document.write( "(10 choose 4) AND THEN (6 choose 2) AND THEN (4 choose 3)\r\n" );
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document.write( "C(10,4)·C(6,2)·C(4,3) = 210·15·4 = 12600\r\n" );
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document.write( "(10 choose 3) AND THEN (7 choose 2) AND THEN (3 choose 3)\r\n" );
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document.write( "C(10,3)·C(7,4)·C(3,2) = 120·35·3 = 12600\r\n" );
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document.write( "(10 choose 3) AND THEN (7 choose 2) AND THEN (3 choose 3)\r\n" );
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document.write( "C(10,3)·C(7,2)·C(5,4) = 120·21·5 = 12600\r\n" );
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document.write( "(10 choose 3) AND THEN (7 choose 2) AND THEN (3 choose 3)\r\n" );
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document.write( "C(10,2)·C(8,4)·C(4,3) = 45·70·4 = 12600\r\n" );
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document.write( "(10 choose 3) AND THEN (7 choose 2) AND THEN (3 choose 3)\r\n" );
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document.write( "C(10,2)·C(8,3)·C(5,4) = 45·56·5 = 12600\r\n" );
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document.write( "Edwin
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