Question

How can I solve this problem using series: A man is trying to lose weight by jogging x miles each day. He sets himself to jog 3 miles the first day, and 4% more than the previous day as he goes along. His goal is to jog 50 miles.

Answer 1

So far this is all I've got 3+3(1.04)+3(1.04)^2+3(1.04)^3+...

Answer 2

So I came up with this equation \[3\sum_{0}^{k}1.04^{k}\ge50\]

Answer 3

I know that if r, the common ratio of a series lies between -1 and 1, then I can use a/(1-r), but what if r is greater than 1?