SOLUTION: Find the sum of the first 28 terms of the sequence {an} = {8n+2}

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Question 1094697: Find the sum of the first 28 terms of the sequence {an} = {8n+2}
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!

The first term is 8(1)+2 = 10; the 28th term is 8(28)+2 = 226.
There are 28 terms; and, because there is a common difference between the terms, the average of all the terms is the average of the first and last terms.
And then the sum of all the number is that average, multiplied by the number of terms.

%2810%2B226%29%2F2+=+118 <-- average of all the terms
118%2A28+=+3304 <-- sum of all 28 terms