document.write( "Question 662130: express given sums in summation notation: 11+15+19+23+...+71 \n" ); document.write( "
Algebra.Com's Answer #411971 by ewatrrr(24785)\"\" \"About 
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document.write( "Hi,
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document.write( "express given sums in summation notation: 11+15+19+23+...+71
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document.write( "Arithemetic Sequence:  d = 4
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document.write( "\"a%5Bn%5D+=+11+%2B+%28n-1%29d+=+71\" 
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document.write( "  11 + (n-1)4 = 71
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document.write( "    4n - 4 = 60
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document.write( "         n = 16
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document.write( "\"a%5Bn%5D+=+11+%2B+%28n-1%294+=++4n+%2B+7\" 
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document.write( "11+15+19+23+...+71 is \"sum%28+4n%2B7%2C+n=1%2C+16+%29\" \n" );
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