Question

I JUST NEED THE ANSWER. What is the sum of a 7-term geometric series if the first term is -11, the last term is -45,056, and the common ratio is -4?

Answer 1

@jigglypuff314

Answer 2

Sorry but I don't really know how to do this :/
I think how you're supposed to do it is along the lines of:
The sum of the terms can be written as follows:
Sn = a(r^n - 1)/(r - 1)
where a = first term, r = common ratio and r ≠ 1, and n=the term u want.
(use this formula when r < 1)