SOLUTION: what is the sum of the integers from -10 to 50?

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Question 932721: what is the sum of the integers from -10 to 50?
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
what is the sum of the integers from -10 to 50?
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-10 to 50 inclusive --> 61 integers
The center integer is (-10 + 50)/2 = 20
View it as 30 pairs + 20
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For each pair,
-10 + 50 = 40
-9 + 49 = 40
etc
--> 30*40 + 20
= 1220