Creating Dartboard with Donuts only

Hello everyone,

I have here an exercise to create a Dartboard with just Donuts, limits (0,0)(24,18) GRID=1, SNAP=.125.  Here below what is needed to reproduce.

Now, I have set the center at 30,20, and with the followings:

Layer 1, for the Donut's inner circle with 0 and 0.62 Outer Diameter;

Layer 2, for the next Donut simply 1.50 DIA;

Layer 3, for the Donut 1.50 and 7.50 Outer diameter;

Layer 4, for the Donut 7.50 and 8.25 OD;

Layer 5, for the Donut 8.25 and 13.00 OD;

0, for the outside is just a circle to place the numbers (Not Donut).

Having done to this stage, I got stuck, just going round and round getting nowhere. I wonder if someone out there could kindly help me out, please.

Here is my attempt (Note that the red radial lines are arrayed around the circle, and done lastly before the numbering):

Thank you in advance. 

Seiji