Which spreadsheet would be used to compute the first five partial sums of the arithmetic series?
a_n = 7(n - 1) - 12
http://i.imgur.com/S16lNG7.png

I think that the answer is the first choice, but I would love confirmation from someone on here. I think this because it uses multiplications (not exponents), and also because it uses A1-A5 rather than N1-N5; I think that this suggests using the term number rather than the term itself. My confusion comes in on the third column, labelled "C." I never learned about this and don't know what it means.

Question

Which spreadsheet would be used to compute the first five partial sums of the arithmetic series?
a_n = 7(n - 1) - 12
http://i.imgur.com/S16lNG7.png

I think that the answer is the first choice, but I would love confirmation from someone on here. I think this because it uses multiplications (not exponents), and also because it uses A1-A5 rather than N1-N5; I think that this suggests using the term number rather than the term itself. My confusion comes in on the third column, labelled "C." I never learned about this and don't know what it means.

anonymous · Answer

When solving for the value of C, it never matches the value of B. So I'm leaning toward the first one because you can't have C1 without there first being B1.