document.write( "Question 199877: This is the last problem that i missed on my exam please help me .. so I will have it straigh for my final. thank you T-Aun\r
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\n" ); document.write( "\n" ); document.write( "How many different ways are there for an admissions officer to select a group of 6 college candidates from a group of 15 applicants for an interview? \r
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Algebra.Com's Answer #150245 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Unfortunately, the previous solution is incorrect. Why? They're not looking for a probability, they just want to know the number of possible combinations.\r
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\n" ); document.write( "\n" ); document.write( "We could use the counting principle to solve this problem, but we'll have overlap and the sample space is far too large. So let's do it this way:\r
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\n" ); document.write( "\n" ); document.write( "In this case, order does NOT matter since the candidates have no rank over one another (ie one isn't president or secretary). \r
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\n" ); document.write( "\n" ); document.write( "Since order does not matter, we must use the <a rel=nofollow HREF=http://www.mathwords.com/c/combination_formula.htm>combination formula</a>:\r
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\n" ); document.write( "\n" ); document.write( "\"n%21%2F%28n-r%29%21r%21\" Start with the combination formula.\r
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\n" ); document.write( "\n" ); document.write( "\"15%21%2F%2815-6%29%216%21\" Plug in \"n=15\" and \"r=6\"\r
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\n" ); document.write( "\n" ); document.write( "\"15%21%2F9%216%21\" Subtract \"15-6\" to get 9\r
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\n" ); document.write( "\n" ); document.write( "\"%2815%2A14%2A13%2A12%2A11%2A10%2A9%2A8%2A7%2A6%2A5%2A4%2A3%2A2%2A1%29%2F9%216%21\" Expand 15!\r
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\n" ); document.write( "\n" ); document.write( " Expand 9!\r
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\n" ); document.write( "\n" ); document.write( " Cancel\r
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\n" ); document.write( "\n" ); document.write( "\"%2815%2A14%2A13%2A12%2A11%2A10%29%2F6%21\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "\"%2815%2A14%2A13%2A12%2A11%2A10%29%2F%286%2A5%2A4%2A3%2A2%2A1%29\" Expand 6!\r
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\n" ); document.write( "\n" ); document.write( "\"3603600%2F%286%2A5%2A4%2A3%2A2%2A1%29\" Multiply 15*14*13*12*11*10 to get 3,603,600\r
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\n" ); document.write( "\n" ); document.write( "\"3603600%2F720\" Multiply 6*5*4*3*2*1 to get 720\r
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\n" ); document.write( "\n" ); document.write( "\"5005\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So 15 choose 6 (where order doesn't matter) yields 5,005 unique combinations\r
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\n" ); document.write( "\n" ); document.write( "This means that there are 5,005 different ways to select a group of 6 college candidates from a group of 15 applicants for an interview (where the order of the candidates doesn't matter).\r
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