SOLUTION: Find the sum of the arithmetic series 100 + 102 + 104...+248 + 250

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Question 481469: Find the sum of the arithmetic series 100 + 102 + 104...+248 + 250
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

arithmetic series 100 + 102 + 104...+248 + 250, d = 2

a%5Bn%5D=a%5B1%5D%2B%28n-1%29%2Ad

250=+100%2B%28n-1%29%2A2

    150/2 + 1 = n

         76 = n

S%5Bn%5D+=%28n%2F2%29%28a%5B1%5D+%2B+a%5Bn%5D%29

S%5B76%5D+=%2876%2F2%29%28100+%2B+250%29+=+76%2A350%2F2%29=+13%2C300