Question 172042
Can you help with this problem using a formula? 
Find the sum of the even integers between -50 and 200 including them, that is, -50+(-48)+(-46)+...+198+200. 
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That's a total of 126 numbers. 1 + (200 - (-50))/2 = 126

The average is (200 + (-50))/2 = 75.
So the total is 126*75 = 9,450.