document.write( "Question 894167: Use Gauss'e approach to find the following sum (Do not use formulas):\r
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Algebra.Com's Answer #541828 by Edwin McCravy(20059)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "We have these 12 terms to add:\r\n" );
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document.write( "3+9+15+21+27+33+39+45+51+57+63+69\r\n" );
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document.write( "The 1st and 12th terms have sum  3+69 = 72\r\n" );
document.write( "The 2nd and 11th terms have sum  9+63 = 72\r\n" );
document.write( "The 3rd and 10th terms have sum 15+57 = 72\r\n" );
document.write( "The 4th and  9th terms have sum 21+51 = 72\r\n" );
document.write( "The 5th and  8th terms have sum 27+45 = 72\r\n" );
document.write( "The 6th and  7th terms have sum 33+39 = 72\r\n" );
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document.write( "That's 6 times 72 or 432.\r\n" );
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document.write( "Edwin
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