SOLUTION: how do you find the sum of all the odd integers between 38 and 78?

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Question 769841: how do you find the sum of all the odd integers between 38 and 78?
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 78
is +%28+78%2F2+%29%5E2+=+1521+
The sum of the odd integers from 1 to 38
is +%28+38%2F2+%29%5E2+=+361+
+1521+-+361+=+1160+
This works for small sequences like
1,2,3,4,5,6,7,8 so I think it's right