document.write( "Question 849384: A partial sum of the arithmetic series is given. Find the sum: 3 + 5 + 7 + . . . + 101. \n" ); document.write( "
Algebra.Com's Answer #511517 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( "d = 2
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document.write( " \"a%5Bn%5D=a%5B1%5D%2B%28n-1%29%2Ad\"    Finding which 'n'  for 101 
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document.write( "  \"a%5Bn%5D=+3%2B%28n-1%29%2A2+=+101\"
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document.write( "          2n + 1 = 101,  n = 50
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document.write( "\"S%5Bn%5D=%28n%28a%5B1%5D%2Ba%5Bn%5D%29%29%2F2\"
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document.write( "\"S%5B50%5D=%2850%283%2B101%29%29%2F2\"= 2600
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document.write( "Following may also be used
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document.write( "\"S%5Bn%5D=%28n%2F2%29%282%2Aa%5B1%5D%2B+%28n-1%29d%29\"
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