But on an even more serious note, this topic is known as Arithmetic and Geometric Progression (APGP), it used to be in the A-math syllabus, but was removed and placed in the C-math (now H2 math) syllabus. To me, not a good choice, as this topic is extremely important in Calculus, especially since the idea of Riemann Integration is still taught at H2 level. If I had my way, relative velocity would go, and this would be in A-math. But then, I don't have my way.
Anyway, here is my solution, which I did find on Saturday night itself. Pretty straight forward, you will need to know a few formulas (involving sigma notation) to simplify the solution to it's final form.
