document.write( "Question 612242: find the sum of each arithmetic series
\n" ); document.write( "-4+1+6+...+91\r
\n" ); document.write( "\n" ); document.write( "13+20+27+...+272\r
\n" ); document.write( "\n" ); document.write( "89+86+83+...+20\r
\n" ); document.write( "\n" ); document.write( "8+11+14+...+23 \n" ); document.write( "
Algebra.Com's Answer #385446 by ewatrrr(24785)\"\" \"About 
You can put this solution on YOUR website!
 
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document.write( "Hi, 
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document.write( "find the sum of each arithmetic series:  
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document.write( "Note: \"a%5Bn%5D=a%5B1%5D%2B%28n-1%29%2Ad\"  and \"S%5Bn%5D=%28n%28a%5B1%5D%2Ba%5Bn%5D%29%29%2F2\"
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document.write( " \"highlight%28-4%29\" +1+6+...+ \"highlight%2891%29\"    || d= 5 
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document.write( "91 = -4 + (n-1)5 
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document.write( "n = 20 
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document.write( "\"S%5Bn%5D=%28n%28-4%2B+91%29%29%2F2=+%2887n%29%2F2+=+870\" 
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document.write( "13+20+27+...+272  ||d = 7
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document.write( "89+86+83+...+20   ||d = -3
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document.write( "8+11+14+...+23    ||d = 3 \n" );
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