



 
Hi Krista. In an arithmetic series, every term is separated from its neighbours So the first five sums of the terms are: You know that the sum of the first 5 numbers is 500, so: and that the sum of the first 4 numbers is 8, so Now you have two equations with two unknowns. You can solve this and find the actual values of A and D. From those, Hope this helps,  


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