document.write( "Question 321468: Please help me answer by finding the sum of the following sequence of numbers:
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Algebra.Com's Answer #230229 by Edwin McCravy(20054) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Two methods:\r\n" );
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document.write( "Method 1:\r\n" );
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document.write( "The sum is twice the sum 1 + 2 + ... + 150, so there\r\n" );
document.write( "are 150 terms.\r\n" );
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document.write( "Here is how to do it without using any formulas:\r\n" );
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document.write( "Let S represent the sum.  \r\n" );
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document.write( " S =   2 +   4 +   6 +   8 + ... + 294 + 296 + 298 + 300\r\n" );
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document.write( "Under that write the sum of the 150 terms in descending order:\r\n" );
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document.write( " S =   2 +   4 +   6 +   8 + ... + 294 + 296 + 298 + 300\r\n" );
document.write( " S = 300 + 298 + 296 + 294 + ... +   8 +   6 +   4 +   2 \r\n" );
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document.write( "Add them term by term:\r\n" );
document.write( " S =   2 +   4 +   6 +   8 + ... + 294 + 296 + 298 + 300\r\n" );
document.write( " S = 300 + 298 + 296 + 294 + ... +   8 +   6 +   4 +   2 \r\n" );
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document.write( "2S = 302 + 302 + 302 + 302 + ... + 302 + 302 + 302 + 302\r\n" );
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document.write( "Therefore since there are 150 terms, there are 150 302's on the right,\r\n" );
document.write( "so \r\n" );
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document.write( "2S = 150*302\r\n" );
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document.write( "2S = 45300\r\n" );
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document.write( " S = 22650\r\n" );
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document.write( "Method 2:\r\n" );
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document.write( "Using formulas for an arithmetic series:\r\n" );
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document.write( "Edwin

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