document.write( "Question 314469: The sum of all of the integers from 1 to 30 is 465. The sum of all of the integers from 1 to 30 that are divisible by 3 is\r
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Algebra.Com's Answer #224846 by Edwin McCravy(20065)\"\" \"About 
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The sum of all of the integers from 1 to 30 is 465. The sum of all of the integers from 1 to 30 that are divisible by 3 is
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document.write( "3 + 6 + 9 + 12 + 15 + 18 + 21 + 24 + 27 + 30 = 165, choice (D)\r\n" );
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document.write( "or do it by the formula for the sum of an arithmetic series,\r\n" );
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document.write( "with first term = \"a%5B1%5D=3\", common difference \"d=+3\", nth term = \"a%5Bn%5D=30\"\r\n" );
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document.write( "\"a%5Bn%5D+=+a%5B1%5D+%2B+%28n-1%29%2A3\"\r\n" );
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document.write( "\"30+=+3+%2B+%28n-1%29%2A3\"\r\n" );
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document.write( "\"27+=+%28n-1%29%2A3\"\r\n" );
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document.write( "\"27%2F3+=+%28%28n-1%29%2A3%29%2F3\"\r\n" );
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document.write( "\"9+=+n-1\"\r\n" );
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document.write( "\"10=n\"\r\n" );
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document.write( "Then use the sum formula:\r\n" );
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document.write( "\"S%5Bn%5D=%28n%2F2%29%28a%5B1%5D%2Ba%5Bn%5D%29\"\r\n" );
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document.write( "\"S%5B10%5D=%2810%2F2%29%283%2B30%29\"\r\n" );
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document.write( "\"S%5B10%5D=%285%29%2833%29\"\r\n" );
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document.write( "\"S%5B10%5D=165\", choice (D)\r\n" );
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document.write( "Edwin
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