document.write( "Question 236340: What is the smallest integer that could be part of a set of two or more positive consecutive integers whose sum is 100?
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Algebra.Com's Answer #173988 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
I believe the number is 9\r
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\n" ); document.write( "\n" ); document.write( "9 sum 9
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\n" ); document.write( "13 sum 55
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\n" ); document.write( "\n" ); document.write( "I summed the numbers from 1 up to when i got past 100.\r
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\n" ); document.write( "\n" ); document.write( "I then looked at each number over 100 to see if there were sums in the lower range of numbers that I could subtract to get 100.\r
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\n" ); document.write( "\n" ); document.write( "When I got to the sum of the number at 16 was 136, I saw that the sum of the numbers at 8 totaled 36 so I could subtract the first 8 numbers from the set and my total from 9 to 16 would equal 100.\r
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\n" ); document.write( "\n" ); document.write( "It worked although I don't have a formula to apply to it.\r
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\n" ); document.write( "\n" ); document.write( "The formula for the sum of an arithmetic progression can be applied.\r
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\n" ); document.write( "\n" ); document.write( "It is:\r
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\n" ); document.write( "\n" ); document.write( "S = n*(x+y)/2 where\r
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\n" ); document.write( "\n" ); document.write( "x = first number in the sequence
\n" ); document.write( "y = last number in the sequence.\r
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\n" ); document.write( "\n" ); document.write( "For this progression, we have:\r
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\n" ); document.write( "\n" ); document.write( "n = 8
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\n" ); document.write( "y = 16\r
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\n" ); document.write( "\n" ); document.write( "the formula becomes:\r
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\n" ); document.write( "\n" ); document.write( "S = 8*(9+16)/2 which becomes:\r
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\n" ); document.write( "\n" ); document.write( "S = 8*25/2 = 100\r
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\n" ); document.write( "\n" ); document.write( "Our solution became:\r
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\n" ); document.write( "\n" ); document.write( "S = 16*(1+16)/2 - 8*(1+8)/2 which became:\r
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\n" ); document.write( "\n" ); document.write( "S = 8*17 - 4*9 = 136 - 36 = 100\r
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\n" ); document.write( "\n" ); document.write( "I suspect there's a generic formula in there to help solve this problem a little more rigorously using algebra, but I don't have that answer for you.\r
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\n" ); document.write( "\n" ); document.write( "The answer, however, is correct as best as I can determine, and it is:\r
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\n" ); document.write( "\n" ); document.write( "The smallest number in a consecutive series that adds up to 100 is 9.\r
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\n" ); document.write( "\n" ); document.write( "The number of numbers involved is 8.\r
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