can someone help me with this math problem?

Question

there are 4 circles of horses on the merry go round. Each circle is 3 feet from the next circle. The radius of the inner circle is 6 ft.
If a horse in the inner circle is 5/6 of the way around the merry go round, give its polar coordinates

Answer 1

Lets pick the origin as the point the horse is at. therefor the coordinates of the horse are (0,0)
Don't like that? Ok lets pick the origin as the center with the zero degree axis intersecting the horse's position (6,0) = (r,Θ).
Still don't like it? Well lets keep the origin as the center but make the zero degree line 5/6ths of the way around (which way I don't care) so now we have (6, 360/6) = (6 ft,60°) or (6, 300°) you pick.

Answer 2

Sorry, but it is difficult to visualize the situation you are trying to describe. What is the inner circle? I assume the other three circles of 4 horses each are outer circles. Are all four circles of horses rotating at the same time the merry-go-round is rotating? How do you define the distance from one circle to another?

A picture of what you are trying to describe is an absolute necessity. As far as I can see, what you are describing is impossible.