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[sportywarbz]

Find the sum of the even integers between 21 and 99.
AND
Find g(1) + g(2) + g(3) + . . . + g(50), given that g(x) = 13 - 5x.

I know that there is something that I can do on my calculator. I also know that there is an equation for this but I can't find it in my notes! Help please!!

 

[Denis]

Find the sum of the even integers between 21 and 99.

Please post in proper section next time; your problem is not "Finance/Business"

Formula: n(n + 1)
Example, n = 3: 2 + 4 + 6 = 3(4) = 12

You need sum (2,4, ... to 98) minus sum(2,4, ... to 20)

OK?

 

[sportywarbz]

My class is a finance/business math course. That's why I posted it here. Thank you though.