SOLUTION: Find the sum of all odd integers between 28 and 232.

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Question 1057961: Find the sum of all odd integers between 28 and 232.
Found 2 solutions by Alan3354, josmiceli:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find the sum of all odd integers between 28 and 232.
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29 to 231 inclusive --> (231 - 29)/2 + 1 = 102 numbers
--> 51 pairs:
29 + 231 = 260
31 + 229 = 260
etc
51*260 = 13260

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The sum of the odd integers from 1 to n
is +S+=+k%5E2+
The k_th odd integer is +n+
then +k+=+%28+n+%2B+1+%29%2F2+
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The sum of the odd integers from 1 to 232 is
+S+=+%28%28+231+%2B+1%29%2F2%29%5E2+
+S+=+%28+232%2F2+%29%5E2+
+S+=+116%5E2+
-----------------------
The sum of the odd integers from 1 to 28 is:
+S+=+%28+%28+27+%2B+1+%29%2F2%29%5E2+
+S+=+14%5E2+
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The sum of the odd intgers between 28 and 232 is
+116%5E2+-+14%5E2+=+13456+-+196+
+13456+-+196+=+13260+ answer
Get another opinion on this if you can.
I'm not 100% sure.