a post is driven into the ground. the first strike drives the post 30 inches into the ground. the next strike drives the post 27 inches into the ground. assume these distances form a geometric sequence, what is the total distance the post is driven into the ground after 8 strikes (to the nearest inch)? What is the maximum distance the post could be driven.
evidently r = .9
S8 = 30(1-.9^8)/.1 = 170.86