document.write( "Question 203306: What is the value of the sum –1 + 2 – 3 + 4 – 5 + 6 – 7 …+10,000?
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Algebra.Com's Answer #153379 by stanbon(75887)\"\" \"About 
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What is the value of the sum –1 + 2 – 3 + 4 – 5 + 6 – 7 …+10,000?
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\n" ); document.write( "Each successive pair sums to \"1\"
\n" ); document.write( "There are 5000 pairs
\n" ); document.write( "The total sum is 5000
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\n" ); document.write( "OR
\n" ); document.write( "Add the positive terms: 2+4+6+...+10000
\n" ); document.write( "S(5000) = (5000/2)(2+10000) = 5000*5001
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\n" ); document.write( "Add the negative terms: 1+3+5+...+9999
\n" ); document.write( "S(5000) = (5000/2)(1+9999) = 2500*10000
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\n" ); document.write( "Subtract the sum of the negatives from the sum of the positives to get:
\n" ); document.write( "5000*5001 - 2500*10000 = 5000
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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